Chapter No 1
Electronic Data Processing
ELECTRONIC DATA PROCESSING (E.D.P)
Electronic data processing (EPD) is the process of collecting data and processing them to produce meaningful information by using computers, processing software and standard database tools. It is the latest technique for processing large amount of data. It is a fast, efficient, and reliable technique.
Some Examples of E.D.P
§ Students Admission or Examination System
§ Payroll System
§ ATM System
§ Stock Control System
§ Electronic Fund Transfer
§ Ticket Buying System
Elements of E.D.P
§ Hardware
§ Software
§ Procedure
§ Personnel is
1.1 - BASIC OVERVIEW OF COMPUTER
1.1.1- COMPUTER
The term computer is derived from the word compute. The word compute means to calculate. A computer is an electronic machine that accepts data from user as input, processes that data by performing calculations and operations on it, stores data for later retrieval and generates the desired output results (information) as illustrated in figure 1.1.
Data Processing Cycle
1.1.2 - DATA & ITS TYPES
Data
A collection of raw facts and figures is called data. These facts can be the numbers, words, images, audio, measurements, and observations. The word raw means that the facts have not yet been processed to get their actual meanings.
Examples
· Each student's test score is one piece of data.
· A product purchased by a customer is also piece of data.
TYPES OF DATA
There are different types of data that may consist of numbers, text, symbols, images, videos, and voice.
1. Numeric Data
Numeric data consists of positive or negative numbers that may also be integer without any fractional part or real number which includes integers with fractions. Numeric type data is usually used for calculations.
|
Examples of Integer numbers |
Examples of Real numbers |
|
12, 256, -23, -87 |
3.1415, -5.40, 7.86 |
2. Alphabetic Data
Alphabetic data contains the letters a, b, c… up to z. These letters may be small or capitals. Alphabets are basic part of any human language. In real life everything is called with its name and every name made up with alphabets.
Examples of Alphabetic Data
Islamabad, Farhan, Table, Office, College, TEVTA, computer etc
3. Alphanumeric Data
Alphanumeric data is combination of alphabets, numbers, special characters (symbols) and space character.
Examples of Alphanumeric Data
Year 2015, Roll No 15EA04, $46, 0330-1234567
4. Graphic Data
Graphics includes pictures, snaps, drawings, charts and moving pictures (movies) etc.
5. Audio Data
Audio includes any type of voice that may be Naats, songs, human voice, etc.
1.1.3 - DATA PROCESSING
Data Processing is central part in computer system. Processing is the stage where the input data is manipulated in order to produce meaningful information. Processing can include several stages such as sorting, searching, calculations, graphing etc.
1.1.4 - INFORMATION
Information is the data produced by computer after processing. The use of information is to have decisions.
Information is also defined as processed, organized, useful, purified and meaningful form of data.
Example
The average score of a class or of the entire school is information that can be derived from the given data.
1.1.5 - INFORMATION TECHNOLOGY (IT)
Information technology (IT) refers to anything related to computing technology, such as networking, hardware, software, the Internet, or the people that work with these technologies.
1.2 - CHARACTERISTICS OF COMPUTER
Following are some of the main characteristics of computer.
PROCESSING SPEED
Speed is one of the main characteristics of a computer. A computer can perform billions of calculations in a second. The speed of a computer is measured in Mega Hertz (MHz) or Giga Hertz (GHz). For example, multiplying 434 and 675 can take a couple of minutes if a human performs such calculations, but computer can perform millions of such calculations in a fraction of second.
ACCURACY
Computers can perform operations and process data faster but with accurate results and no errors. Results can be wrong only if incorrect data is fed to the computer.
DATA STORAGE
A computer can store large amount of data. This data can be used/search at any time and from any location. The storage capacity of computer is measured in Mega Bytes, Giga Bytes and Tera Bytes up to Yotta Bytes.
VERSATILE
Computer is a versatile machine. They are used in various fields. They are used in banks, business companies, Schools & Colleges, at hospitals, at government organizations and at home for entertainment & work purposes.
COMMUNICATION
Computers have the ability to communicate. Two computers can be connected to send & receive data using communication devices and media. Special software are used for text and video chat. Anyone having computer can connect over the internet to visit websites and share files, photos & videos online.
MULTITASKING
Computers can perform several tasks at a time. For example, you can listen to songs, download movies, and prepare word documents all at the same time.
1.3 - TYPES OF COMPUTER
There are three types of computers
1- ANALOG COMPUTERS
Analog computers are used to process analog data. Analog data is of continuous nature and which is not discrete or separate. Such type of data includes temperature, pressure, speed weight, voltage, depth etc. These quantities are continuous and having an infinite variety of values.
Analog computers are used to in making and in chemical industry and oil refinery etc where flow and temperature measurements are important.
2- DIGITAL COMPUTERS
Most of the computers available today are digital computers. Digital computers process the digits to represent numerals, letters, or other special symbols. Digital computers operate on inputs which are ON-OFF type, and its output is also in the form of ON-OFF signal. Normally, an ON is represented by a 1 and an OFF is represented by a 0. It is also known as binary 1 or 0.
Examples of digital electronic computers include the IBM PC, calculators, the Apple Macintosh as well as modern smartphones.
3- HYBRID COMPUTERS
A hybrid is a combination of digital and analog computers. It combines the best features of both types of computers, i-e. It has the speed of analog computer and the memory and accuracy of digital computer.
Hybrid computers for example are used for scientific calculations, in defense and radar systems, In Intensive Care Unit (ICU) to measure patient’s blood pressure and temperature etc.
1.4 - CLASSIFICATION OF COMPUTER
Digital computers can be classified into four categories
· Super Computers
· Mainframe Computers
· Minicomputers
· Micro Computers
1- SUPER COMPUTERS
Super computers have been designed for optimum processing power and overall speed. As of 2017, there are supercomputers which could perform up to quadrillions typical calculations within seconds. Super computers are used to solve complex scientific and statistical applications like weather forecasting, airflow, simulations, guided missiles, atomic explosions, and satellites etc. CRAY-XP, NEC-500, Deep Blue are the examples of super computers.
2- MAINFRAME COMPUTERS
A mainframe computer is a very large computer capable of handling and processing very large amounts of data quickly. The working speed of this computer measures in Millions Instructions per Second.
Mainframe is multi-user server computer that can serve up to 50,000 users simultaneously.
They are used by large institutions, such as government agencies and large corporations, banks, educational institutions, research laboratories, financial institutions, and sophisticated atomic research etc.
3- MINICOMPUTERS
A minicomputer, a term no longer much used, is a computer of a size intermediate between microcomputer and a mainframe.
Typically, minicomputers have been standalone computers (computer systems with attached terminals and other devices) sold to small and mid-size businesses for general business applications.
In recent years, the minicomputer has evolved into the "mid-range server" and is part of a network. IBM's AS/400e is a good example.
4- MICROCOMPUTERS
Microcomputer is complete machine for personal use in home or at office that includes a microprocessor, memory, and input/output (I/O) facilities. These computers are the cheapest among the other three types of computers.
The Micro-computers are specially designed for general usage like entertainment, education and work purposes. Well known manufacturers of Micro-computer are Dell, Apple, Samsung, Sony, and Toshiba.
Desktop computers, Gaming consoles, Sound & Navigation system of a car, Notebooks, Notebooks, PDA’s, Tablet PC’s, Smart-phones, Calculators are all type of Microcomputers.
1.5 - APPLICATIONS OF COMPUTER IN VARIOUS FIELDS
Today computer is playing very important role in every field of life. Many activities in daily life can be performed very easily and quickly. Many fields where computers are widely used that includes
BUSINESS
Today, in global markets, it is impossible to run the business without the use of computer technology. Many business activities are performed very quickly and efficiently by using computers. The administrative paperwork is also reduced by using computers. Many business use websites to sell their products and contact their customers.
EDUCATION
Computers are used in teaching and research. The students can solve different kinds of problems quickly and efficiently by using computers. They can also collect different information on the Internet.
BANKS
Computers are widely used in banks. They are used in banks for record keeping and maintaining accounts of customers. By the ATM facility the customers can draw money through ATM card from any branch of that bank (or another bank) at any time of a day.
ENTERTAINMENT
Computers are also playing very important role for the entertainment. Nowadays, computer can be used to watch TV programs on the Internet. People can also watch movies, listen to music, and play games on the computer.
HOME
At home, computer is used to maintain personal records and to access much other information on the Internet. People can also use computer at home for making home budgets etc.
MEDICAL
Nearly every area of the medical field uses computers. For example, computers are used for maintaining patient history & other records. They are also used for patient monitoring and diagnosis of diseases etc.
DEFENSE
Computers are the main tools which help in developing missiles and other equipment as well as designing and maintenance in the deference system. Computer builds the links between the soldiers and commanders through the satellite.
DESIGNING & PUBLISHING
Computers aid in designing buildings, magazines, prints, newspapers, books, and many others. The construction layouts are designed beautifully on system using different tools and software.
GOVERNMENT DEPARTMENTS/OFFICES
Computer is used in government offices for communication, data processing and project management. Like businesses and individuals, computers are almost essential part of federal and provincial government offices for their daily office operations.
1.6 - APPLICATIONS OF COMPUTER IN ENGINEERING, EDUCATION AND BUSINESS
1.6.1 - COMPUTER IN ENGINEERING
Engineering designers require effective means of collecting, storing, retrieving, processing, communicating, distributing, displaying, plotting, and printing large quantities of information. Computers are used in engineering for the following purposes
USE OF CAD SOFTWARE
One of the major uses of computer technology in engineering is with CAD software. Computer aided design software is the application of computer technology for logical designing. This industrial art is now widely used in many traditional industries, such as automobile manufacturing, ship building, aerospace, prosthetics, architectural projects, and even special effects in movies.
USE OF CFD SOFTWARE
CFD (Computational Fluid Dynamics) software are used to virtually test airplane and automobiles etc. Using a computer, engineers can immediately calculate such effects without having to physically test them.
PROBLEM SOLVING
Computers can perform complex calculations much quicker than a human can. They can also be used to simulate situations to make the right decisions.
AUTOMATION
It is almost impossible for humans to perform the same task repeatedly with no variation. So, when a company needs hundreds of products that look and behave identically, they tend to use computers and robots to construct them.
1.6.2 – COMPUTER IN EDUCATION
Computer technology has a deep impact in the education sector to make learning easier and much more interesting.
Here is detail of some areas of education where computer has great impacts.
INSTRUCTIONS TO STUDENTS
Lecture delivering using PowerPoint slides, Word documents or Web pages is very useful for better concept and clarity. Computer can help in improving pronunciation of students by using microphones, headphones, speakers, specially prepared software, and special dedicated websites. Video conferencing, chat and email may also be used for communication among instructors and students for e-learning.
STUDENTS LEARNING
Students can use computers to collect notes, pictures, and videos from web pages for detailed information to manage their projects or assignments. A saved soft copy of documents can be used in future.
EXAMINATION AND EVALUATION
Examination and evaluation of students can be easily done using computer because it may facilitate to keep records of students for their academic scores as well as their grade, personal history about exams etc. Question bank for students can be created for online testing and evaluation.
LIBRARY
Electronic library is more helpful for students/faculty members where documents, magazines, journals, brochures, and research articles are stored as soft copy. Furthermore, special library software can be used in existing library to keep record of books as well as issues and returns of the books.
INSTITUTE ADMINISTRATION
The administration of the institute can use computer to store student’s personal, academic, and financial records. Similarly accounts of the institution and records of employees also can be stored.
1.6.3 – COMPUTER IN BUSINESS
Computers are used for all aspects of running a business. Here is detail of these aspects as follows
BUSINESS COMMUNICATION
In this era companies are using email, live chat systems, online meeting tools, video conferencing system and smart phones for communication among employees, suppliers, and customers.
INVENTORY MANAGEMENT SYSTEM
Inventory management system is used to track the quantity of each item a company maintains in its stock.
PAYROLL SYSTEM
Computerized payroll system is used in different organizations to maintain pay account of employees, easily and quickly.
DATA MANAGEMENT
Today, most companies store digital versions of documents on servers (large computers) and storage devices, these documents can be easily available geographically via internet.
MANAGEMENT INFORMATION SYSTEM
Management Information System (MIS) enables companies to track sales data, expenses, productivity level, profitability, losses, identify areas of improvements and strategic decisions.
HUMAN RESOURCE MANAGEMENT
Computerized HRM helps for the better human resource planning, recruitment, wages and salary planning, personnel record keeping, training and development.
1.7 - COMPONENTS OF COMPUTER SYSTEM
Computer system can be divided into following parts
· Computer Hardware
· Computer Software
1.6.1 - COMPUTER HARDWARE
Hardware represents the physical and tangible components of a computer i.e. the components that can be seen and touched. These components include keyboard, mouse, memory, processor, disks, disk drives, display screens, printers, speakers, mother boards, and chips etc.
1.6.2 - COMPUTER SOFTWARE
Software represents the logical or intangible parts of computer. Software is collection of different programs. A program is set of electronic instructions that tell the computer what to do and how to do a particular task.
Software is developed in a computer programming language.
Software can be categorized according to what it is designed to accomplish. Different software's are used to solve different problems. There are two major software categories, the system software and the application software or apps.
1.6.3 - BLOCK DIAGRAM OF COMPUTER
Computer hardware further divided into following three units as described and shown below in diagram.
Block Diagram of Computer
· Input Unit: deals with input devices, these devices are used to feed data into computer. Six widely used input devices are keyboard, mouse, scanner, microphone, digital camera, web cam.
· Output Unit: consists of output devices which are used to deliver processed information. Four widely used output devices are monitor, printer, plotter and speakers.
· System Unit: The system unit is a case consists of electronic components of the computer that provide data processing and storage facility. Some important devices house in this unit are CPU, RAM, mother board, hard disk, CD drive etc.
1.8 - INPUT & OUTPUT DEVICES
Input and output devices are used to interact with the computer system. Input devices let you to transfer data and user command into the computer system. Mostly used input devices are keyboard, mouse, touch pad, scanner, microphone, joystick, and digital camera etc.
On the other hand, output devices display the result of input data or signals after processing it. Examples of these could be your computer’s monitor, printer, plotter, and speakers.
1.8.1 - INPUT DEVICES
KEYBOARD
The keyboard is one of the primary ways we communicate with the computer and enter data. The most widely used layout in the English language is called QWERTY. A standard desktop computer keyboard contains 101 to 105 keys as shown in below figure.
There are many different types of computer keyboards, including wired, wireless, ergonomic, and multimedia.
Desktop Computer Keyboard
TYPES OF KEYS
Alphabetic Keys
All the letters on the keyboard A-Z, either may be small or capitals.
Numeric Keypad
Numeric keypad is located on the right side of the keyboard and consists of keys having numbers (0 to 9) and mathematical operators (+ − * /) defined on them. This keypad is provided to support quick entry for numeric data.
Punctuation Keys
All the keys associated with punctuation such as the comma, period, semicolon, brackets, and parenthesis etc. Also, all the mathematical operators such as the plus sign, minus sign, and equal sign etc.
Special Keys
All the other keys on the computer keyboard such as the control keys, arrow keys, caps lock key, delete key etc.
Cursor Movement Keys
These are arrow keys and used to move the cursor in the direction indicated by the arrow (up, down, left, right).
Function Keys
Function keys labeled F1 to F12. These keys have different meaning depending on which program is running.
MOUSE
A mouse is the most widely used pointing device with a GUI (Graphical User Interface) environment on personal computers. A mechanical mouse has a rubber ball on its underside to detect movement of the mouse. An optical mouse uses devices that emit and sense light to detect the mouse's movement. A cordless mouse (either mechanical or optical) transmits data using wireless technology.
Some common mouse operations are point, click, right click, double click, drag and rotate wheel etc.
TRACK BALL
Track Ball is an input device like a mouse. It is used in Lap top computers to control motion of pointer on screen. It is a pointing device like upside down mouse. It has a ball on its upper side. This ball is moved by fingers or thumb and the pointer moves accordingly on screen.
TOUCH PAD
Touch pad is a pointing input device. It is used in Lap top computers to control motion of pointer on screen. Touch pad is a stationary input device. It has a flat surface of 1.5 to 2 square inch. Finger is moved on this surface to move pointer on screen.
JOYSTICK
Joystick is an input device used to play games on computer. It is used to control motion of an object quickly in game with the help of a handheld stick.
This stick can be moved forward, backward, or sideways. The buttons called the triggers. Joystick also used occasionally for CAD/CAM systems.
SCANNER
Scanner is important input device of a computer system. A scanner converts printed documents into images. Some types of scanners scan documents and produce the results in black & white images. The scanner operates in the same manner as a photocopier.
MICROPHONE
Microphone is an input device used to enter voice data into the computer. Computer microphones are used for a variety of purposes, from recording audio, voice chatting, teleconferencing to video conferencing.
TOUCH SCREEN
A touch screen is display screen that enables the user to interact with the computer by touching areas on the screen. It allows the user to interact with a device without a mouse or keyboard and is used with smart phones, tablets, and computer screens. Touch screen is used in ATM and in latest smart phones to receive input from the user.
DIGITAL CAMERA
Digital Cameras are used to capture images. Those images are then transferred to a computer when the Camera is connected to the computer. Mostly the Digital Camera images are in JPEG format.
BIOMETRIC DEVICES
A biometric device is security devices which are used for identification and authentication. These devices have various methods to verify or recognize a person on behalf of physiological or behavioral features. There are so many features to recognize a person: that includes, Fingerprints, Facial images, Iris and Voice recognition.
1.8.2 - OUTPUT DEVICES
MONITOR
Monitor or display screen is most important output device. It is used to display the video and graphics information generated by the computer through the video card. Monitors are very similar to televisions but with higher resolution. Figure below shows different types of monitors.
Different Types of Monitor
TYPES OF MONITORS
According to technology, size, weight, price, and picture quality following monitors are widely used in computer.
CRT
CRT (short for Cathode Rays Tube) monitors look much like old-fashioned televisions and are very deep in size. It works by moving an electron beam produced by picture tube across the back of the screen.
LCD
LCD (Liquid Crystal Display) monitors are much thinner, use less energy, and provide a greater graphics quality. LCD technology can be mostly found in portable devices like digital watches, tablets, and smart phones etc. It is also offered in full size monitor as alternatives to CRT monitors.
The technology works by passing an electric current through liquid crystal which is contained between two sheets of polarizing material.
LED
LED (Light-Emitting diode) is a semiconductor light source used as indicator lamp in many devices. It is simple a LCD that uses LEDs for back lighting, which creates images/Pictures in display devices like TV.
PLASMA
Plasma Display Panel (PDP) is flat panel display. They contain small cells containing electrically charged ionized gases, when electrical current pass through the phosphors it lights up themselves to create the image on the screen.
PRINTERS
A printer is an output device that prints characters, symbols and graphics, on paper. The printed output is called hard copy.
There are two types of printers Impact Printers & Non-Impact Printers.
|
Impact Printers |
Non-Impact Printers |
|
Old printing technology |
Modern printing technology |
|
These printers produce print on paper by striking mechanism. |
These printers produce print on paper by non-striking mechanism. |
|
This type of printers uses pins, hammer, or wheel to strike against an inked ribbon to print on a paper. |
This type of printers uses laser, sprays of special ink and pressure to print on paper |
|
Normally impact printers use continuous paper sheet |
Non-impact printers normally use individual paper sheet. |
|
Impact printers are normally less expensive. |
Non-impact printers are more expensive |
|
Printing quality is poor |
Printing quality is fine |
|
Slow speed printers |
Fast speed printers |
|
These are very noisy because they strike printing head. |
These printers do not make a noise due to non-striking mechanism |
|
Examples of Impact printers are Dot Matrix, Line printer and Daisy wheel. |
Examples of Non-Impact printers are, Laser and Inkjet printers. |
(A) - IMPACT PRINTERS
Impact type printers used pins and hammer that strikes against the paper through ribbon. Printing quality of impact printer is not good, it creates noise while printing. The impact printers are used where low-cost printing is required.
Three common forms of impact printers (figure below) are as follows
· Dot matrix printers
· Daisy wheel printer
· Line printer
DOT MATRIX PRINTER
Dot matrix printer creates characters by striking pins against an ink ribbon. Each pin makes a dot, and combinations of dots form characters. The dot-matrix printer uses print heads containing from 9 to 24 pins. Dot-matrix printers are inexpensive and typically print at speeds of 100-600 characters per second.
Impact Printers
DAISY WHEEL PRINTER
Like a ball-head typewriter, the printer uses a metal or plastic disk containing each of the letters, numbers, and other characters it supports. When something is printed, the printer rotates the disk to each character and then using a hammer strikes each character into an ink ribbon to create the character on paper.
LINE PRINTER
Line printer contains a chain of characters or pins that print an entire line at one time. Line printers are very fast but produce low-quality print. They can typically print the range of 1,200 to 6,000 lines per minute. Drum, chain, and band printers are line printers.
(B) - NON-IMPACT PRINTERS
A non-impact printer prints characters and graphics on paper without striking paper. Some printers use sprays ink while others use heat and pressure to create images. These printers are costly but faster and having no noise during printing. Different kinds of non-impact printers (see below figure) are as follows
· LASER printer
· Inkjet printer
· Thermal printer
LASER PRINTER
LASER is short for Light Amplification by Stimulated Emission of Radiation. Laser printer uses the same technology as photocopy machines and produce very high-quality text and graphics. The speed of laser printers is high, and they print quietly without producing much noise. Many home-use lasers printers can print eight pages per minute, but faster and print approximately 21,000 lines per minute, or 437 pages per minute if each page contains 48 lines.
Non-Impact Printers
INKJET PRINTER
Ink-jet printers form characters on paper by spraying ink from tiny nozzles through an electrical field that arranges the charged ink particles into characters at the rate of approximately 250 characters per second. The ink is absorbed into the paper and dries instantly. Various colors of ink can also be used.
PLOTTERS
Plotter (figure 1.20) is hardcopy output device used to print large linear drawings. The drawing or design is conveyed to the paper surface by plotting a serial of points and connecting them with lines. Plotters are most often used for drafting or map making. It can produce full color renderings as well as geometric line drawings.
SPEAKERS
A speaker is a softcopy output device that plays sound generated by the computer. They are usually in a group of two and come in various sizes and shapes. You can listen to songs which are stored on the hard disk of the computer through the speaker.
Headphones give sound output produced by the computer. They are like speakers, except they are worn on the ears, so only one person can hear the output at a time.
MULTIMEDIA PROJECTOR
A multimedia projector is a compact, high resolution, full-color projector capable of projecting text, images, video, and audio content. Typically, the projector will feature inputs for a computer, DVD player, storage device, TV cable.
1.9 – PROCESSOR & ITS TYPES
The system unit is a case consists of electronic components of the computer that provide data processing and storage facility. Some important devices house in this units are CPU, RAM, mother board, hard disk, CD drive etc.
CPU (Central Processing Unit)
CPU or central processing unit is a chip considered as the brain of the computer. It is also called processor.
It performs all types of data processing operations. It stores data, intermediate results, and instructions (program). It controls the operation of all parts of computer. Figure shows the CPU for personal computers.
COMPONENTS OF CPU
CPU itself has following three components
1. Arithmetic Logic Unit)
2. Control Unit
3. Memory or Storage Unit
1. ARITHMETIC LOGIC UNIT (ALU)
This unit consists of two subsections namely
· Arithmetic section
· Logic Section
Arithmetic Section
Function of arithmetic section is to perform arithmetic operations like addition, subtraction, multiplication, and division. All complex operations are done by making repetitive use of above operations.
Logic Section
Function of logic section is to perform logic operations such as comparing, selecting, matching, and merging of data.
2. MEMORY OR STORAGE UNIT (MU)
These are high speed memory locations built into CPU. The memory registers temporarily hold the program instructions for the program to be executed, the input data to be processed and the intermediate results of any calculations when the processing is being done.
3. CONTROL UNIT (CU)
This unit controls the operations of all parts of computer. It is responsible for controlling the transfer of data and instructions among other units of a computer. It manages and coordinates all the units of the computer. It communicates with Input / Output devices for transfer of data or results from storage.
1.10 – MEMORY & MEMORY UNITS
1.10.1 – BIT & BYTE
BIT
A bit (short for BInary digiT) is the smallest unit of data/information that can be stored or manipulated in a computer. A bit can have a binary value of either 0 or 1.
Binary means that there are only two logical choices or states i.e. True / false or on / off. A bit can be a tiny magnetic region on a hard disk, a tiny dent on a CD or DVD, or a tiny transistor on a memory stick.
BYTE
A byte is a set of 8 bits that represent a single character in the computer's memory. Bytes are used to measure file sizes, hard disk space, and computer memory. Larger amounts of data are measured in units such as megabytes, gigabytes, and terabytes. For example, one kilobyte is equal to 1,024 bytes. The short form of a byte is an upper-case B.
The table below shows the memory units, their abbreviations and number of bytes equivalent to each memory unit.
|
Memory Unit |
Abbreviation |
Number of Bytes |
|
Bit |
b |
0 or 1 |
|
Byte |
B |
8 bits |
|
Kilo Byte |
KB |
1024 Bytes |
|
Mega Byte |
MB |
1024 KB |
|
Giga Byte |
GB |
1024 MB |
|
Tera Byte |
TB |
1024 GB |
|
Peta Byte |
PB |
1024 TB |
|
Exa Byte |
EB |
1024 PB |
|
Zetta Byte |
ZB |
1024 EB |
|
Yotta Byte |
YB |
1024 ZB |
1.10.2 - PRIMARY MEMORY
Primary memory is accessible directly by the processing unit. RAM, ROM, and Cache are examples of primary memory.
1. RAM - (Random Access Memory)
RAM is main memory of computer. It is referred to as random access memory (RAM) because it is randomly select and use any location of the memory directly store and retrieve data.
It is also called read/write memory. The storage of data and instructions inside the primary storage is temporary. All data and instructions disappear from RAM as soon as the power to the computer is switched off because it is the type of volatile memory.
TYPES OF RAM
D-RAM
Dynamic Random-Access Memory is the more common type. It is slower because it needs to be refreshed thousands of times per second. DRAM supports access times of about 60 nanoseconds. It is an inexpensive memory.
S-RAM
Static Random-Access Memory is faster than DRAM in term of speed because it does not need to be refreshed. SRAM can give access times as low as 10 nanoseconds.
Despite SRAM being faster, it is not as commonly used as DRAM because it is so much more expensive.
2. ROM
ROM (read-only memory) refers to special memory chip used to store programs that boot the computer and perform diagnostics. The ROM can only be read by the CPU, but it cannot be changed.
The basic input/output system (BIOS) program is stored in the ROM that examines and initializes different equipment attached to the PC when the switch is made ON. ROM is type of non-volatile memory.
PROM
PROM is programmable read only memory. PROM allows the data to be loaded by the user, but it can be written only once. Once a program has been written onto a PROM, it remains there forever.
EPROM
EPROM (Erasable programmable read only memory) is a special type of PROM that can be erased by exposing it to ultraviolet light. Once it is erased, it can be reprogrammed. An EPROM is like a PROM but requires only ultraviolet light to be erased.
EEPROM
Pronounced e-e-prom, an EEPROM (Electrically erasable programmable read only memory) is a special type of PROM that can be erased by exposing it to an electrical charge. Like other types of PROM, EEPROM retains its contents even when the power is turned off. Also, like other types of ROM, EEPROM is not as fast as RAM.
3. CACHE MEMORY
Cache memory, also called CPU memory, is static type random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. This memory is typically integrated directly with the CPU chip or placed on a separate chip that has a separate bus interconnect with the CPU.
Cache memory is a small-sized type of volatile computer memory that provides high-speed data access to a processor and stores frequently used computer programs, applications, and data. It stores and retains data only until a computer is powered up.
1.10.3 – SECONDARY STORAGE DEVICES
Secondary storage devices are used to store data and instructions permanently. These devices also called auxiliary storage or external storage. These are non-volatile storage that is not under the direct control of a computer's central processing unit (CPU).
Secondary storage devices can be divided into 3 groups, which are as follows
1. MAGNETIC SECONDARY STORAGE DEVICES
This type of devices used magnetic technology to store and access data. Floppy Disk/Drive, Hard Disk Drive, and Magnetic Tape are examples of magnetic secondary storage devices.
FLOPPY DISK
The floppy disk was introduced by IBM in 1971. It was officially called “diskette”. FD is removable storage medium that consists of a thin and flexible magnetic disk inside a plastic carrier. The floppy disk drive or FDD is a piece of computer hardware that reads data from, and writes data to, a floppy disk. The 3.5 inches floppy disk can store 1.44 MB data.
HARD DISK DRIVE
The hard disk is also called fixed disk. It consists of one or more metal plates. Metal plates are coated with magnetic material to store data.
Each platter is broken up into tracks and sectors. Tracks are concentric circles on the disk; each track is broken up into a series of sectors. A motor rotates disks. There is also an access arm and read / write heads to read and write data on disks. Hard disks are available in different size like 150 GB, 300 GB and more up to Tera Bytes.
MAGNETIC TAPE
Magnetic tape is the oldest storage device. It is made of plastic coated with magnetic material. Tape drive is used to read and write data on tape. Magnetic tape is sequential access device. It is slower device than magnetic disk or optical disk. Usually magnetic tapes are used to take data backups.
2. OPTICAL SECONDARY STORAGE DEVICES
This type of devices used optical technology to store and access data. CD, DVD and BD are examples of magnetic secondary storage devices.
CD
CD (Compact Disk) is type of optical storage media that is used to hold prerecorded text, graphics, and sound. CD-ROM is a read-only disk. Read only means the disk’s content is recorded at the time of manufacture and cannot be written on or erased by the user. A CD-ROM disk can hold up to 700 MB of data, equal to 300,000 pages of text.
CD drive/writer is used to play/write CDs. CD drive use a combination of lasers and sensors to read the data stored on the surface of the compact disks. Types of CDs are CD-ROM, CD-R (recordable) and CD-RW (re-writeable)
DVD
DVD (digital video disk) or (digital versatile disk) is a type of optical disk technology similar to the CD-ROM. It can hold up to 17 GB of data, about 25 times an ordinary CD-ROM. For this reason, a DVD-ROM can store a large amount of multimedia software and complete movies in different languages. It can also play music CDs and CD-ROMs.
DVDs are read-only devices. To avoid this limitation, companies also produce DVD-R/DVD-RW disks and DVD-burners.
BD – (BLU RAY DISK)
This disk is developed by Blu-ray disc association (that includes Apple, Hitachi, HP, LG, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony). Blu-ray Disc see figure (BD) is an also an optical disc storage medium designed to supersede the DVD format.
BD-ROM (read only) for reading recorded content, BD-R (recordable) for PC data storage, BD-RW (rewritable) is used for PC data storage. Single layer BD Can hold data up to 25/27 GB, Double layer BD can hold data up to 50 GB.
3. MICROCHIP BASED SECONDARY STORAGE DEVICES
SSD
SSD stands for Solid-State Drive, a type of PC storage that is faster than a hard drive. SSDs, store data on microchips rather than platters that makes them significantly faster, quieter, and cooler than standard hard drives. However, they are very expensive than hard disks. SSDs are best suited for high-performance applications that need extra speed and reliability.
USB FLASH DRIVE
A flash drive is a small, ultra-portable storage device which, unlike an optical drive or a traditional hard drive, has no moving parts.
Flash drives connect to computers and other devices via a built-in USB port, Flash drives are often referred to as pen drives; thumb drives or jump drives. It can store several MB’s to GB’s of data.
1.11 - COMPUTER SOFTWARE
Software represents the logical or intangible parts of computer. Software is collection of different programs. A program is series of instructions that tells the computer what to do and how to do accomplish a particular task. Software is developed in a computer programming language. The Two major software categories are system software and application software.
1.11.1 – SYSTEM SOFTWARE
A program or set of programs that is especially designed to control different operations of computer system is called system software. It controls the working of different components of the computer. The system also enables
the other application programs to execute properly.
Operating systems, utility programs, and device drivers are the examples of system software. Operating system is the main and most popular type of system software.
1.11.2 – APPLICATION SOFTWARE
A program or set of programs that are especially designed to solve the specific problems of users, are called application software. It is also known as software package.
There are Different kinds of application software such as commercial software, scientific software, financial packages, Games, multimedia software.
CATEGORIES OF APPLICATION SOFTWARE
The application software are divided into two main categories
1. Custom-built software
2. Packaged software
1. Custom Built Software
Software that is developed for a particular customer or organization is called custom built software. For example, software developed to maintain the records of students at a particular college is category of custom-built software.
2. Packaged Software
The software that is developed for sale to the public is called packaged software. Packaged software is used to solve some common problems of many people or users. Some examples of packaged software are
1. Word processor such as MS-Word and Word Perfect
2. Spreadsheet such as MS-Excel
3. Presentation software such as MS- Power Point and Apple Keynote
4. Database software such as MS-Access, SQL Server, and Oracle
5. Graphic software such as Adobe Photoshop, CorelDraw, and AutoCAD
6. Communication Software such as Internet Explorer and Google Chrome etc
7. Entertainment software such as Windows Media Player and VLC Media Player
8. Web development software such as MS-Expression, Adobe Dreamweaver, and Net-Objects Fusion etc.
1.12 – PROGRAMMING LANGUAGES
A language used to write instructions for the computer is called programming language. Programming language use vocabulary and set of grammatical rules for instructing a computer to perform specific tasks
1.12.1 - TYPES OF PROGRAMMING LANGUAGES
There are three main kinds of programming language:
· Machine language
· Assembly language
· High-level language
1. MACHINE LANGUAGE
Machine language is a low-level programming language. It is easily understood by computers but difficult to read by people, therefore people use higher level programming languages. Programs written in high-level languages are also either compiled and/or interpreted into machine language so that computers can execute them.
2. ASSEMBLY LANGUAGE
An assembly language consists of a set of symbols and letters. A translator is required to translate the assembly language to machine language. This translator program is called the 'Assembler.' It is use terms like MOVE, ADD, SUB and END.
3. HIGH-LEVEL LANGUAGE
A high-level language is a computer programming language that resembles natural language or mathematical notation and is designed to reflect the requirements of a problem. Languages such as C, C++, BASIC, PHP, Python, JavaScript, C# and Java are all high-level languages. Advantages of high-level languages are that they are very readable and portable. These languages require a compiler or interpreter to translate into a form that a particular machine understands.
Exercise
Short Questions
1. What does E.D.P stands for?
E.D.P stands for Electronic Data Processing
2. Define the electronic data processing
Electronic Data Processing is the use of computers in recording, classifying, manipulating, and summarizing of the data.
3. Define computer
The term computer is derived from the word compute. The word compute means to calculate. A computer is an electronic machine that accepts data from user as input, processes that data by performing calculations and operations on it, stores data for later retrieval and generates the desired output results (information)
5. Define data
A collection of raw facts and figures is called data. These facts can be the numbers, words, images, audio, measurements, and observations. The word raw means that the facts have not yet been processed to get their actual meanings.
6. What are the types of data?
There are different types of data that includes numeric data, alphabetic data, alphanumeric data, graphic data, and voice data.
7. Define the numeric data
Numeric data consists of positive or negative numbers that may also be integer without any fractional part or real number which includes integers with fractions.
8. Define the alphabetic data
Alphabetic data contains the letters a, b, c… up to z. These letters may be small or capitals.
9. Define the alphanumeric data
Alphanumeric data is combination of alphabets, numbers, special characters (symbols) and space character.
10. Define the data processing.
Data processing can include several stages such as sorting, searching, calculations, graphing etc. where the input data is manipulated in order to produce meaningful information.
11. Define the information
Information is the data produced by computer after processing. The use of information is to have decisions.
12. Define the information technology
Information technology (IT) refers to anything related to computing technology, such as networking, hardware, software, the Internet, or the people that work with these technologies.
13. Define the analog computers
Analog computers recognize and process the data as a continuous measurement of a physical property (voltage, pressure, speed, and temperature). Automobile speedometer, analog clock, voltage meter, ampere meter and electric current meter are examples of analog computer.
14. Define the digital computers
Digital computers process the digits to represent numerals, letters, or other special symbols. Digital computers operate on inputs which are ON-OFF type, and its output is also in the form of ON-OFF signal. Normally, an ON is represented by a 1 and an OFF is represented by a 0. It is also known as binary 1 or 0.
15. Define the hybrid computers
A hybrid is a combination of digital and analog computers. It combines the best features of both types of computers, i-e. It has the speed of analog computer and the memory and accuracy of digital computer.
16. What are the categories of digital computer regarding classification?
Digital computers can be classified into four categories
· Super Computers
· Mainframe Computers
· Minicomputers
· Micro Computers
17. Define the micro computers
Microcomputer is complete machine for personal use in home or at office that includes a microprocessor, memory, and input/output (I/O) facilities.
18. Define the computer hardware
Hardware represents the physical and tangible components of a computer i.e. the components that can be seen and touched. These components include keyboard, mouse, memory, processor, disks, disk drives, display screens, printers, speakers, mother boards, and chips etc.
19. Define the computer software
Software represents the logical or intangible parts of computer. Software is collection of different programs. A program is set of electronic instructions that tell the computer what to do and how to do a particular task.
20. Define the input unit
The input unit deals with input devices, these devices are used to feed data into computer. Six widely used input devices are keyboard, mouse, scanner, microphone, digital camera, web cam.
21. Define the output unit
The output unit is used to deliver information from the computer to an external or output device. Four widely used output devices are monitor, printer, plotter and speakers.
22. Define the system unit
The system unit is a case consists of electronic components of the computer that provide data processing and storage facility. Some important devices house in this units are CPU, RAM, mother board, hard disk, CD drive etc.
23. Define the keyboard
The keyboard is one of the primary ways we communicate with the computer and enter data. It is used to enter three most widely used types of data i.e. numeric data, alphabetic data, and alphanumeric data.
24. What is the most widely used layout for keyboard?
QWERTY is the most widely used keyboard layout in English language for computer keyboard.
25. Define the pointing input devices
The input devices used to move the pointer (arrow) on screen are called pointing input devices. The major pointing devices are the mouse for the desktop computer and the touchpad for the laptop. Track ball and pointing stick are also pointing input devices used by small number of users.
26. What are types of mouse?
There are two types of mouse; a mechanical mouse has a rubber ball on its underside to detect movement of the mouse. An optical mouse uses devices that emit and sense light to detect the mouse's movement.
27. What are some common operations of mouse?
Some common mouse operations are point, click, right click, double click, drag and rotate wheel etc.
28. Define the scanner
A scanner is input device that captures images from photographic prints, posters, magazine pages etc for computer editing and display. The scanner operates in the same manner as a photocopier.
29. Define the microphone
Microphone is a device that converts sound waves into analog electrical waves. Computer microphones are used for a variety of purposes, from recording audio, voice chatting, teleconferencing to video conferencing.
30. Define the touch screen
A touch screen is a computer display screen that is also an input device. The screens are sensitive to pressure; a user interacts with the computer by touching pictures or words on the screen.
31. Define the output devices
An output device is any device used to send data from a computer to another device or user. Most computer data output that is meant for humans is in the form of audio or video.
32. Define the monitor
Monitor or display screen is most important output device. It is used to display the video and graphics information generated by the computer through the video card. Monitors are very similar to televisions but with higher resolution.
33. What is CRT stands for?
CRT stands for Cathode Rays Tube
34. What is LCD stands for?
LCD stands for Liquid Crystal Display
35. What is LED stands for?
LED stands for Light Emitting Diode
36. Define the printer
A printer is an output device that prints characters, symbols, and graphics, on paper.
37. Define the term hard copy
A hard copy is a printed copy of information from a computer. Sometimes referred to as a printout, a hard copy is so-called because it exists as a physical object.
38. What are two major types of printers according to their technology?
The two major types of printer according to their technology are
· Impact printers
· Non-Impact printers
39. Write some names of impact printers
The Dot Matrix printer, the Line printer, and Daisy Wheel printer
40. Write some names of non-impact printers
The LASER printer, Inkjet printer, and Thermal Wax printer
41. How many pins are there in Dot Matrix heads?
There are 9 to 24 pins in Dot Matrix heads.
42. Which unit is used to measure the speed of Dot Matrix printer?
The working speed of Dot Matrix printer is measured in CPS (characters per second)
43. Why the Line printer is called Line printer?
The Line printer prints an entire line at one time.
44. What is LASER stands for?
LASER is short for Light Amplification by Stimulated Emission of Radiation.
45. What is the speed of LASER printer?
Home-use laser printers can print eight pages per minute, but faster and print approximately 21,000 lines per minute or 450 pages per minute.
46. Define the plotter
A plotter is hardcopy output device used to print large linear drawings.
47. Define the speakers
A speaker is a softcopy output device that plays sound generated by the computer.
48. Define the System Unit
The system unit is a case consists of electronic components of the computer that provide data processing and storage facility.
49. What is CPU stands for?
CPU stands for Central Processing Unit
50. What is the job of CPU in computer system?
It performs all types of data processing operations. It stores data, intermediate results, and instructions (program). It controls the operation of all parts of computer.
51. What are components of CPU?
CPU itself has following three components
· Arithmetic Logic Unit)
· Control Unit
· Memory or Storage Unit
52. What is ALU stands for?
ALU stands for Arithmetic Logic Unit
53. What is the job of ALU?
The purpose of the ALU is to perform mathematical operations such as addition, subtraction, multiplication, and division. Additionally, the ALU processes basic logical operations like AND/OR calculations. Also known as the arithmetic logic unit, it serves as the computational hub of the Central Processing Unit (CPU) for a computer system.
54. What is MU stands for?
MU stands for memory unit
55. What is the function of Memory Unit?
Functions of the memory unit are −
§ It stores all the data and the instructions required for processing.
§ It stores intermediate results of processing.
§ It stores the final results of processing before these results are released to an output device.
§ All inputs and outputs are transmitted through the main memory.
56. What is the function of Control Unit (CU)?
This unit controls the operations of all parts of computer. It is responsible for controlling the transfer of data and instructions among other units of a computer. It manages and coordinates all the units of the computer. It communicates with Input / Output devices for transfer of data or results from storage.
57. What is difference between primary and secondary memory?
The memory which is directly accessible by processing unit (CPU) is called primary memory and the memory which is not directly accessible by processing unit (CPU) is called secondary memory.
58. What is RAM stands for?
RAM stands for Random Access Memory
59. Why the RAM is referred to as random access memory?
It is referred to as random access memory (RAM) because it is randomly select and use any location of the memory to store and retrieve data.
60. What is difference between volatile and non-volatile memory?
Volatile memory is also called as temporary memory as it will hold memory temporarily. Non-Volatile Memory: A device which can hold data in it even if it is not connected to any power source is called Non-Volatile Memory.
61. Define the DRAM
Dynamic Random-Access Memory is the more common type. It is slower because it needs to be refreshed thousands of times per second. DRAM supports access times of about 60 nanoseconds. It is an inexpensive memory.
62. Define the SRAM
Static Random-Access Memory is faster than DRAM in term of speed because it does not need to be refreshed. SRAM can give access times as low as 10 nanoseconds. Despite SRAM being faster, it's not as commonly used as DRAM because it's so much more expensive.
63. What is ROM stands for?
ROM stands for Read Only Memory
64. What is the function of ROM?
ROM is used to store programs that boot the computer and perform diagnostics.
65. What is BIOS stands for?
BIOS stands for Basic Input Output System.
66. What is PROM stands for?
PROM stands for Programmable Read Only Memory
67. What is EPROM stands for?
EPROM stands for Erasable Programmable Read Only Memory
68. What is EEPROM stands for?
EEPROM stands for Electrically Erasable Programmable Read Only Memory
69. Define the BIT
A bit (short for BInary digiT) is the smallest unit of data/information that can be stored or manipulated in a computer. A bit can have a binary value of either 0 or 1.
70. Define the Byte
A byte is a set of 8 bits that represent a single character in the computer's memory. Bytes are used to measure file sizes, hard disk space, and computer memory. Larger amounts of data are measured in units such as megabytes, gigabytes, and terabytes.
71. Define the secondary storage devices
Secondary storage devices are used to store data and instructions permanently. These devices also called auxiliary storage or external storage.
72. What is CD stands for?
CD stands for Compact Disk
73. What is DVD stands for?
DVD stands for Digital Versatile Disk or Digital Video Disk
74. What is BD stands for?
BD stands for Blu Ray Disk.
75. Define the Solid-State Drive
SSD stands for solid-state drive, a type of PC storage that is faster than a hard drive. An SSD can read and write data much faster than a mechanical hard drive.
76. Define the USB Flash Drive
Flash drive is the solid-state storage module that plugs into the computer's USB port. Using flash memory chips that hold up to one terabyte of data. USB drives are extremely popular for backup as well as data transfer from one machine to another.
77. Define the software
Software represents the logical or intangible parts of computer. Software is collection of different programs. A program is series of instructions that tells the computer what to do and how to do accomplish a particular task. Software is developed in a computer programming language.
78. What are major types of software?
There are two major software categories the system software and application software.
79. Define the system software
A program or set of programs that is especially designed to control different operations of computer system is called system software. It controls the working of different components of the computer. The system also enables the other application programs to execute properly.
80. Write some popular operating systems names
Windows and DOS by Microsoft, Macintosh by Apple, UNIX and Linux, Solaris by Sun Microsystems are some popular operating systems.
81. Define the application software
A program or set of programs that are especially designed to solve the specific problems of users, are called application software.
82. What are categories of application software?
The application software are divided into two main categories
· Custom-built software
· Packaged software
83. Define the custom-built software
Software that is developed for a particular customer or organization is called custom built software. For example, software developed to maintain the records of students of a particular college is category of custom built software.
84. Define the packaged software
The software that is developed for sale to the public is called packaged software. Packaged software is used to solve some common problems of many people or users.
85. Define the language translator
A Compiler is a computer program that translates code written in a high-level language to a lower level language, object/machine code. The most common reason for translating source code is to create an executable program
Multiple Choice Questions with Key
1. The term computer is derived from the word _________
a. commute b. compute c. calculate d. copter
2. Computer accepts input in form of ___________
a. data b. information c. input d. all of these
3. Collection of raw _______________ is called data.
a. metals b. trees c. facts & figures d. grain
4. Numeric data contains ___________ numbers
a. positive b. negative c. integer d. all of these
5. Alphabetic data contains __________________
a. alphanumeric b. alphabets c. numbers d. none of these
6. Alphanumeric data contains ____________________
a. numbers b. alphabets c. symbols d. all of these
7. Graphic data contains _______________
a. pictures b. drawings c. charts d. all of these
8. The purpose of data processing is to produce ________________
a. data b. information c. input d. none of these
9. Information is the ________________
a. processed data b. meaningful data c. useful data d. all of these
10. The use of information is to have ________________
a. output b. decisions c. input d. processing
11. The speed of computer is measured in ______________
a. kilos b. meters c. bytes d. hertz
12. The storage capacity of computer is measured in _____________
a. bytes b. cycles c. data d. hertz
13. Computers can perform several tasks at a time; this feature is known as
a. multi-national b. multi-tasking c. multi-color
d. multi-media
14. Analog computers are used to process _____________ data.
a. electronic b. digital c. analog d. graphic
15. Analog computes can process _______________
a. temperature b. pressure c. speed d. all of these
16. Digital computers process the digits, which are called ____________digits
a. binary b. ternary c. unary d. none of these
17. The binary digit 1 represents ON and 0 represents ______________
a. zero b. OFF c. digit d. none of these
18. The most commonly used type of computers is ______________
a. hybrid b. analog c. digital d. none of these
19. Most powerful digital computer is ______________
a. super b. analog c. personal d. digital
20. The computer used in large corporations, banks, government agencies, research
laboratories to manage huge amount of data, is _________ computer.
a. mainframe b. super c. laptop d. notebook
21. The complete computer for personal use in home or at office is known as
a. micro b. super c. mini d. mainframe
22. Examples of personal computers are ________________
a. desktop b. laptop c. palmtop d. all of these
23. A student can use computer for _____________
a. research work b. collecting information c. solving problems
d. all of above
24. Major component of computer are ______________.
a. hardware b. software c. hardware & software
d. none of these
25. All physical and tangible components of computer are called _________.
a. hardware b. software c. data d. none of these
26. All logical and intangible parts of computer are called ______________
a. hardware b. software c. hard disk d. none of these
27. Software is collection of different computer _______________
a. devices b. programs c. information d. none of these
28. A computer program is set of electronic _____________ that tell the
computer what to do and how to do a particular task.
a. devices b. machines c. instructions d. none of these
29. Major software categories are the ______________.
a. application & utility software b. system & business software
c. system & application software d. utility software
30. ______ let you to input data and user command into the computer system.
a. output devices b. memory devices c. storage devices
d. input devices
31. __________ displays the result of input data or signals after processing it.
a. input devices b. output devices c. processing devices
d. memory devices
32. The primary and most important type of input device is ______________.
a. printer b. monitor c. keyboard d. scanner
33. Mouse is type of _________________ devices.
a. pointing input b. processing c. output d. storage
34. Click, right click, double click, drag and rotate wheel are some common operations
done by the _______________.
a. mouse b. keyboard c. joy stick d. light pen
35. __________ is an input device used to enter voice data into the computer.
a. keyboard b. light pen c. microphone d. joystick
36. Touch pad is usually used in ________________ computers.
a. desktop b. palmtop c. laptop d. none of these
37. A _______ is a device that scans images from photographic prints, posters, magazine,
pages, and similar sources for computer editing and display.
a. mouse b. printer c. camera d. scanner
38. A user can interact with computer, smart phones and tablets without a mouse or
keyboard, using ______________.
a. touch pad b. touch screen c. touch stone d. none of these
39. The device used to display soft copy of data and information is ________.
a. monitor b. keyboard c. printers d. plotter
40. Types of monitors are _____________.
a. CRT b. LCD c. LED d. all of these
41. LCD stands for _____________.
a. liquid crystal display b. labour control department
c. least common denominator d. none of these
42. LED stands for _________________.
a. low energy demand b. light emitting diode
c. light emitting display d. none of these
43. CRT stands for _________________.
a. child right trust b. cathode ray tube
c. computer remote terminal d. all of these
44. Number of pixels on computer screen is known as _________________.
a. bit b. picture size c. screen resolution d. mega pixels
45. A printer is an output device that prints ________________ on paper.
a. characters b. symbols c. graphics d. all of these
46. The printed output on papers provided by the computer is called________.
a. hardcopy b. hardware c. softcopy d. head copy
47. The printers used pins and hammer that strikes against the paper through ribbon are
known as _________________.
a. non-impact printers b. impact printers c. ink printers
d. none of these
48. The printers used heat, pressure; laser and ink for printing are known as ________.
a. impact printers b. non-impact printers c. wax printer
d. none of these
49. _______________ printer is example of impact printers.
a. Dot Matrix b. Line c. daisy wheel d. all of these
50. _______________ printer is example of non-impact printers.
a. LASER b. Inkjet c. Thermal Wax d. all of these
51. Printing speed of large laser printer is ______________ pages per minute.
a. 300 b. 200 c. 100 d. 50
52. In laser printer the refillable ink container is called ________________.
a. cartridge b. toner c. carbon ribbon d. none of these
53. In Inkjet printer the refillable ink container is called ________________.
a. cartridge b. toner c. carbon ribbon d. none of these
54. DPI stands for ________________.
a. data processing installation b. dots per inch
c. digital printing and imaging d. none of these
55. The speed of Dot Matrix printer is measured in _____________
a. PPM b. CPM c. CPS d. none of these
56. In printers CPS stands for _______________.
a. cycles per second b. counts per second
c. cost per second d. characters per second
57. In printers PPM stands for ______________.
a. pages per minute b. pay per minute
c. pulses per minute d. points per minute
58. The printers, prints characters and graphics on paper without striking on
paper, are known as __________________.
a. impact printers b. digital printers
c. non-impact printers d. analog printers
59. The printer works like a photo copier machine is known as ______ printer.
a. Laser b. Inkjet c. Dot Matrix d. Line
60. A big size printer used to print maps, documents, posters, large size drawings and
geometric lines is known as ___________________.
a. Inkjet printer b. drawing printer c. plotter d. laser printer
61. CPU stands for ________________.
a. cost per unit b. cash processing unit c. central processing unit
d. none of these
62. The brain of computer is called _______________.
a. hard disk b. CPU c. RAM d. mother board
63. Components of CPU are ________________.
a. ALU b. CU c. MU d. all of these
64. ALU stands for ________________.
a. application layer user b. automatic loading unit
c. arithmetic logic unit d. all logic unit
65. MU stands for _________________.
a. mobile unit b. multi-user c. memory unit d. none of these
66. CU stands for _________________.
a. control unit b. computer unit c. central unit d. none of these
67. The ________________ section of ALU is used to perform arithmetic operations like
addition, subtraction, multiplication, and division.
a. calculative b. logic c. arithmetic d. none of these
68. The ________________ section of ALU is used to perform logic
operations such as comparing, selecting, matching, and merging of data.
a. calculative b. logic c. arithmetic d. none of these
69. The actual execution of instructions happens in __________________.
a. CU b. ALU c. MU d. none of these
70. The memory unit of CPU contains ____________ to hold (temporarily) the data and
instructions to be executed.
a. registers b. units c. houses d. blocks
71. The unit of CPU which controls the operations of all parts of computer is known as
a. memory unit b. control unit c. arithmetic unit d. logic unit
72. The memory which is directly accessible by the CPU is called ________.
a. secondary memory b. temporary memory
c. permanent memory d. primary memory
73. The memory which is not directly accessible by the CPU is called _____.
a. secondary memory b. temporary memory
c. primary memory d. none of these
74. As compare to secondary memory, the primary memory of computer is ______.
a. slow b. cheap c. fast d. large
75. Example of primary memory is ______________.
a. RAM b. Cache Memory c. ROM d. all of these
76. Example of secondary memory is ______________.
a. Hard disk b. Floppy disk c. CD d. all of these
77. RAM stands for ____________.
a. read access memory b. remote access memory
c. random access memory d. real access memory
78. RAM is ____________ memory of computer.
a. main b. permanent c. secondary d. none of these
79. The feature of RAM is _____________.
a. temporary b. volatile c. read/write d. all of these
80. The ____________ RAM is faster.
a. dynamic b. static c. automatic d. none of these
81. ROM stand for ______________.
a. record only memory b. run of memory
c. read only memory d. none of these
82. A memory which requires a power source to hold information is called ____ memory.
a. non-volatile b. tactile c. volatile d. none of these
83. A memory that does not require a connection to a power source to retain information
is called _______________ memory.
a. non-volatile b. tactile c. volatile d. none of these
84. Which is example of volatile?
a. ROM b. BIOS c. PROM d. RAM
85. The basic input/output system (BIOS) program is stored in the ___________ chip.
a. RAM b. cache c. ROM d. none of these
86. BIOS is abbreviation of ______________.
a. Basic Input Output System b. Best Input Output System
c. Basic Input Output Symbol d. Base Input Output System
87. EEPROM stands for ________________.
a. Electrically Erasable Programmable Read Only Memory
b. Electronic Erasable Programmable Read Only Memory
c. Easily Erasable Programmable Read Only Memory
d. Early Erasable Programmable Read Only Memory
88. A ___________ is smallest unit of data/information that can be stored in a computer.
a. boot b. bite c. bit d. none of these
89. A bit can have a binary value of either ______________.
a. 0 or 2 b. 0 or 1 c. 0 or -1 d. none of these
90. The base of binary number system is _______________.
a. 0 b. 1 c. 2 d. 3
91. A byte is set of _______________ bits.
a. 1 b. 2 c. 4 d. 8
92. Bytes are used to measure _______________.
a. file size b. hard disk space c. computer memory
d. all of these
93. 1 kilobyte is equal to _______________.
a. 1000 bytes b. 1024 bytes c. 1024 bits d. none of these
94. Which statement is valid?
a. 1 KB = 8 bytes b. 1 MB = 8KB c. 1 KB = 1024 bytes
d. 1 MB = 1024 bytes
95. Magnetic tape is ______________ device.
a. direct access b. random access c. sequential access
d. fast access
96. Floppy disk is ______________ storage medium.
a. removable b. fixed c. optical d. none of these
97. The 3.5 inches floppy disk can store _______________ data.
a. 1.24 MB b. 1.34 MB c. 1.44 MB d. 1.54 MB
98. Which of the following device can store large amounts of data?
a. Floppy Disk b. Hard Disk c. CDROM d. Zip Disk
99. In hard disks a _____________ is used to read/write data.
a. lens b. head c. disk reader d. none of these
100. When a hard disk undergoes formatting, it is divided into ____________.
a. tracks b. sectors c. both a & b d. none of these
101. CD stands for _____________.
a. control data b. change directory c. compact disk d. car driver
102. A CD can hold up to ______________ MB of data.
a. 900 b. 700 c. 1024 d. 1000
103. A CD _______ disc is a compact disc that can be written, erased, and written again.
a. RW b. ROM c. R d. none of these
104. DVD stands for ______________.
a. direct video disk b. digital versatile disk
c. digital video disk d. both b & c
105. CD, DVD and BD are the ______________ type of storage media.
a. magnetic b. optical c. electrical d. none of these
106. BD stands for ______________.
a. bio disk b. blu ray disk c. binary digit d. bank draft
107. USB Flash drive is often referred to as ________________.
a. jump drive b. pen drive c. thumb drive d. all of these
108. USB stands for ______________.
a. united states bank b. universal serial Bus
c. uniform serial bus d. none of these
109. The software especially designed to control different operations of computer system
are called _______________ software.
a. computer b. application c. system d. none of these
110. Example of system software is ______________.
a. operating systems b. utility programs c. device drivers
d. all of these
111. Example of operating systems is _________________.
a. Windows 10 b. MS Word c. web browser d. anti-virus
112. Software designed to solve the specific problems of users are called_____ software.
a. operating systems b. application c. system d. none of these
113. ______________ is the example(s) of application software.
a. commercial software b. games c. multimedia d. all of these
114. The software that is developed for sale to the general public is called ________.
a. custom-built software b. packaged software
c. public software d. none of these
115. Software that is specially developed for some specific organization or other user are
called_______________ software.
a. custom-built b. packaged c. user d. organization
Answer Key
|
1 |
b |
21 |
a |
41 |
a |
61 |
c |
81 |
c |
101 |
c |
|
2 |
a |
22 |
d |
42 |
b |
62 |
b |
82 |
c |
102 |
b |
|
3 |
c |
23 |
d |
43 |
b |
63 |
d |
83 |
a |
103 |
a |
|
4 |
d |
24 |
c |
44 |
c |
64 |
c |
84 |
d |
104 |
d |
|
5 |
b |
25 |
a |
45 |
d |
65 |
c |
85 |
c |
105 |
b |
|
6 |
d |
26 |
b |
46 |
a |
66 |
a |
86 |
a |
106 |
b |
|
7 |
d |
27 |
b |
47 |
b |
67 |
c |
87 |
a |
107 |
d |
|
8 |
b |
28 |
c |
48 |
b |
68 |
b |
88 |
c |
108 |
b |
|
9 |
d |
29 |
c |
49 |
d |
69 |
b |
89 |
b |
109 |
c |
|
10 |
b |
30 |
d |
50 |
d |
70 |
a |
90 |
c |
110 |
d |
|
11 |
d |
31 |
b |
51 |
a |
71 |
b |
91 |
d |
111 |
a |
|
12 |
a |
32 |
c |
52 |
b |
72 |
d |
92 |
d |
112 |
b |
|
13 |
b |
33 |
a |
53 |
a |
73 |
a |
93 |
b |
113 |
d |
|
14 |
c |
34 |
a |
54 |
b |
74 |
c |
94 |
c |
114 |
b |
|
15 |
d |
35 |
c |
55 |
b |
75 |
d |
95 |
c |
115 |
a |
|
16 |
a |
36 |
c |
56 |
d |
76 |
d |
96 |
a |
|
|
|
17 |
b |
37 |
d |
57 |
a |
77 |
c |
97 |
c |
|
|
|
18 |
c |
38 |
b |
58 |
c |
78 |
a |
98 |
b |
|
|
|
19 |
a |
39 |
a |
59 |
a |
79 |
d |
99 |
b |
|
|
|
20 |
a |
40 |
d |
60 |
c |
80 |
b |
100 |
c |
|
|
Long Questions
1: Define the computer, draw its block diagram
2: Explain the data and its types
3: What is data processing? Differentiate between data and information.
4: What is difference between information and information technology?
5: Explain the characteristics of computer.
6: Explain the types of computer.
7: Describe all computer according to classification
8: What is difference between Mainframe and Microcomputer?
9: Illustrate the application of computer in various fields of life?
10: What are components of computer? Explain input, output & system unit of computer.
11: What are input devices? Name some of the commonly used input devices.
12: Differentiate between input and output devices also describe any two input and two output devices.
13: Explain all the pointing input devices with their use.
14: Write a note on following input devices
1. Keyboard 2. Scanner 3. Microphone 4. Touch Screen
15: What is monitor? Explain different types of monitors.
16: What is printer? Differentiate between impact and non impact printers.
17: Write a note on following:
1. LASER Printer 2. Dot Matrix Printer 3. Line Printer
18: Write a note on following: 1. Inkjet Printer 2. Plotter 3. Speaker
19: What is CPU? Explain its parts.
20: Explain the RAM and its types.
21: What is function of ROM? Explain all types of ROM.
22: Explain the difference between Bit and Byte.
23: Write a short note on following
1. Cache Memory 2. Primary Memory 3. Secondary Memory
24: Write a short note on following
1. Volatile Memory 2. Non-volatile Memory 3. ROM
25: Explain the difference between RAM and ROM.
26: What are output devices? Name some of the commonly used output devices.
27: Write a note on following
1. Floppy Disk 2. Hard Disk Drive 3. Magnetic Tape
28: Write a note on following
1. CD 2. DVD 3. BD 4. USB Flash Drive
29: What is software? Illustrate its types.
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