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1. Differentiate Input and Output device?

Input devices are used for giving input to the computer. But output devices are used to get the result back from the computer. The examples of input devices are keyboard, mouse, scanner, digital camera atc...whereas output devices include monitor, printer, projector etc....

2. Differentiate SRAM and DRAM.


Static RAM stores each bit of data on six metal oxide semiconductor field effect transistors, or MOSFETs. SRAM is used in devices that require the fastest possible data access without requiring a high capacity. Some examples are CPU caches and buses, hard drive and router buffers and printers.


Dynamic RAM stores data using a paired transistor and capacitor for each bit of data. Capacitors constantly leak electricity, which requires the memory controller to refresh the DRAM several times a second to maintain the data.

3. Explain briefly the salient features of the various generation of computers?

Ans:Salient Features of various generations of computer are:
 i) First generation computers used vacuum tubes or valves, which worked on the principle of
 thermionic emission. The vacuum tubes contained filaments which, on heating, emitted
 electrons. Disadvantages of the first generation computers are:
 • Extremely slow compared to the speed of the present day computers.
 • Huge in size and not portable.
 • Needed heavy air conditioning.
 • Costly
 • The system of processing was batch processing.
 ii) Second generation computers replaced vacuum tubes with transistors. The transistors led
 to the development of new electronic hardware, including the first minicomputers.
 Advantages of second generation computers over the first generation ones are:
 • Small size
 • Operation speed relatively high.
 • Portable and robust.
 • Less cost.
 iii) Third generation computers used integrated circuits (ICs). The integrated circuits are
 very small in size, required nominal power. The advantages of this generation of computers
 was that the size decreased considerably and speed was very high. They were portable and
 handy and the cost was also very low.
 iv) Fourth generation computers used more powerful leis. like Medium, large and very large
 scale ICs. The most important electronic device developed during this generation was the
 microprocessor, which led to the development of micro computers. This led to computers
 which are :
 • Very powerful in mathematical calculations and data processing abilities.
 • Very fast, operating in the range of nanoseconds
 • Capable of Multitasking
 • Cheapest among all generation of computers.
 v) Fifth generation computers are thought of to be intelligent ones (using Artificial
 Intelligence) which is lacking in today's computers. They would probably:
 • work in parallel and not serially.

• Do a greater number of tasks at a time.
 • Be faster and more powerful than the fourth generation computers and have large
 • Will do knowledge-processing in addition to data-processing jobs.

4. Explain the cache memory in detail?

Cache memory is a small and fast memory between CPU and main memory. It is extremely fast
 compared to normal memory. Transferring data between main memory and CPU causes delay because
 RAM is slower than CPU. Cache memory stores copies of data from most frequently used main memory
 locations. When processor needs to read from or write to a location in main memory, it first checks
 whether a copy of data is in the cache. If so processor immediately reads or writes to cache. Computers
 use multilevels of cache such as Level1(smallest)and Level2 cache.CPU resident cache is known as L1
 or primary cache (16 to 32 KB) to 512 KB.Cache is also added to mother board also known as L2 cache
 (512 KB to 1024 KB). Higher end systems can have as much as 2 MB of L2 cache on mother board.

5. Explain the different factors affecting the processing speed of CPU?

• Ans: CPU Speed/Clock speed: Speed of CPU also known as clock speed. The clock speed is the
 number of instructions executed by the CPU in one second It is measured in megahertz(million
 instructions per second). The average speed of a new CPU is about 1000MHz to 4000 MHz.(1 to 4 giga
 • Instruction set: The number of instructions decide the efficiency of a CPU. More the instructions , less
 efficient is the CPU and less the instructions, More efficient is the CPU.
 • Word size/Register size: The size of registers determines the amount of data the computer can work
 with at a time. Normally it is 32 bits. Smaller the size of register, slower will be the computer. . It is also
 known as Word size. It varies from 16 bits to 128 bits.
 • Data bus capacity: Width of a data bus determines the largest number of bits that can be transported at
 one time.
 • Cache Memory size: Cache memory is a high speed memory. Greater the cache, faster a processor
 runs. Most modern processors can execute multiple instructions per clock cycle which speeds up a
 program. Some CPU’s have storage for instructions and data built inside the processor chip . This is
 called internal cache or L1 cache memory.
 • Memory Size: The amount of PRIMARY STORAGE (RAM) determines the size of program that can
 be kept in primary storage, which is faster than secondary storage. There by the speed of computer
 increases. The size of RAM varies from 64 MB to 4 GB.

6. Explain the function of light pen and joystick?


Alight pen is an input device that uses a light sensitive stylus connected by a
 wire to a video terminal. The user brings the light pen to the desired point on the screen surface
 and presses a button, causing it to identify the location on the screen. Light pens are used to
 select the options from a menu displayed on screen or to draw images in graphics system by

  “dragging” the cursor around the screen. The pixels (dots) on a display screen are constantly
 being refreshed (re-illuminated) over again. When the user presses the light pen button,
 allowing the pen to sense light, the pixels being illuminated at the movement identifies on the


A joystick is an omni-directional level that is used to move the cursor on screen
 more rapidly then it can be moved with the directional arrow keys. It has a spherical ball at
 its lower end as well as its upper end. The lower spherical ball moves in a socket. Thus, a
 joystick can be moved right or left, forward or backward. The electronic circuitry inside the
 joystick detects and measures the displacement of the joystick from its central position. This
 information is sent to CPU. The pointer on the CRT screen moves according to the position
 of the joystick. The joystick is used extensively in video games, but is also used as an input
 device in computer aided design (CAD) systems.

7. Explain the General Structure of CPU?

Ans: Program counter: This register stores address of next instruction to be executed.
 Memory address register (MAR): This register specifies address in memory where information can be
 found. This register is also used to point to a memory locations where information can be stored.
 Memory buffer register: This register acts as an interface between CPU and memory. When CPU
 issues a Read Memory command, instruction is fetched and placed in MB register.
 Instruction register-This stores a copy of current instruction.
 Instruction decoder (ID): ID is an electronic hardware, which decodes instructions. The instructions are
 further broken down into a set of micro operations, so that they can be executed directly.
 General purpose registers: They are used to store data. There are 6 GP registers. These are used for
 storage of data as needed by the program.
 Arithmetic logic unit: The basic arithmetic operations such as addition,subtraction,multiplication and
 division are carried out here. These operations need atleast two operands, one which is stored in
 accumulator and the other in the MBR. After the manipulation of data in ALU, the result is transferred to
 Accumulator: During processing the intermediate data needed for future processing is stored in
 accumulator. The contents of ACC are used by ALU for operations and later by MBR holds the final
 result for further action.

8. Give the major features of windows 98?

The major features of windows 98 are:
 • Faster than Windows 95: The maintenance wizard of windows 98 checks the hard
 disk for problems and frees its space so that the programs run faster without any
 additional hardware.
 • Web Integration: The interactive content of the Internet is combined with the power
 of computer and improved web features are provided.
 • Improved Reliability: New utilities, wizards and resources are introduced which help
 the computer in running smoothly and efficiently. System file checker of Windows
 98 restores the critical files if they are changed. Scan disk runs automatically if the
 computer is not shut down properly.
 • Multiple Display: Several monitors can be used to run different programs on separate
 • Power management: The computer can be started in few seconds i.e. the start up
 • time is improved. The programs can be restored in their last saved positions.

• More Entertaining: New features like enhanced television, video playback and web
 TV for windows makes computer more entertaining.

9. How a server motherboard different from a desktop?

A server motherboard is different from a desktop in features and performance. The number of processor support, RAM slots ,Expansion card slots etc...are more. For example the Intel® Server Board S5000PSL has the performance and features for growing businesses demand. It provides excellent data protection, and advanced data management. It support 64-bit Multi-Core Intel® Xeon® processor. Eight fully buffered 533/667 MHz DIMMs. Up to six SATA 3Gb/s ports.

10. How does a bar code reader read the data?

A bar code reader is a device used for reading (decoding) bar-coded data. It may be a
 hand-held scanner, or may be embedded in a stationary scanner. It scans a bar-code image
 and converts into and converts in into a alphanumeric value, which is then fed to the
 computer to which the bar-code reader is connected. Just as though the alphanumerical value
 had been typed on a keyboard.
 A bar code reader uses a laser-beam scanning technology. The laser beam is stroked across
 the pattern of bars of a bar-code. Different bar codes having different patterns of bars reflects
 the beam in different ways, which is sensed by a light-sensitive detector. Reflected them
 transmitted to recognition logic circuits which convert in into an alphanumeric value.

11. How is data recorded on a CDROM? How is it read?

CD-ROM (an abbreviation of "Compact Disc read-only memory") is a Compact Disc
 that contains data accessible by a computer. While the Compact Disc format was originally
 designed for music storage and playback, the format was later adapted to hold any form of
 binary data. CD-ROMs are popularly used to distribute computer software, including games
 and multimedia applications, though any data can be stored (up to the capacity limit of a
 disc). Some CDs hold both computer data and audio with the latter capable of being played
 on a CD player, whilst data (such as software or digital video) is only usable on a computer.
 These are called Enhanced CDs. Data is stored on the disc as a series of microscopic
 indentations ("pits", with the gaps between them referred to as "lands"). A laser is shone
 onto the reflective surface of the disc to read the pattern of pits and lands. Because the depth
 of the pits is approximately one-quarter to one-sixth of the wavelength of the laser light used
 to read the disc, the reflected beam's phase is shifted in relation to the incoming beam,
 causing destructive interference and reducing the reflected beam's intensity. This pattern of
 changing intensity of the reflected beam is converted into binary data.

12. No Display. What is the problem?

a)    CPU fan problem

b)    Heat sink related issue

c)    Power related issues

d)    Improper Jumper settings

13. What are cursor control devices? Explain working of any one such Device?

Ans:These are the devices that are used for control of the cursor. They allow the position of
 control on the computer and the functions of the software to be executed. Example: mouse,
 trackball, light pen etc.
 Mouse:- It is a pointing device having a small box with a round ball on the bottom and three
 buttons on the top. The mouse is attached on the terminal by cables. It allows the user to
 manipulate the cursor on the screen. The mouse captures the cursor and the movements of
 mouse control the operations on the computer.

Mouse could be optical, offering quite and reliable operation, or mechanical which is
 cheaper but noisier. User can move the mouse, stop it at a point where the pointer is to be
 located and with the help of buttons, make selection of choices.

14. What are the differences between Multitasking and Multiprocessing?

Multitasking- Enables the processor to do multiple programs simultaneously by fast switching through the programs. Here doesn't have the involvement of multiple processors.

Multiprocessing- Enables the processor to do multiple programs simultaneously by the use of multiple processors.

15. What are the different functions of a computer?

A computer does the following functions;


a) Accepting data


b) Processing Data


c) Storing Data


d) Displaying Data

16. What are the factors affecting the speed of the microprocessor?

The following are the factors affecting the speed of the microprocessor.

a) Number of instructions build in the processor.

b) Bandwidth

c) Clock Speed

d) Number of transistors inside the processor

17. What are the main functions provided by most Operating Systems?

Main functions of an operating system are:
 1. Process management: A process is a program in execution. It is the job which is currently
 being executed by the processor. During its execution a process would require certain
 system resources such as processor, time, main memory, files etc. OS supports multiple
 processes simultaneously. The process management module of the as takes care of the
 creation and termination of the processes, assigning resources to the processes, scheduling
 processor time to different processes and communication among processes.
 2. Memory management: It takes care of the allocation and deallocation of the main
 memory to the various processes. It allocates main and secondary memory to the
 system/user program and data. To execute a program, its binary image must be loaded into
 the main memory.
 OS decides: which part of memory are being currently used and by whom, which process to
 be allocated memory, Allocation and deallocation of memory space.
 3. I/0 management: This module of the as co-ordinates and assigns different I/O devices
 namely terminals, printers, disk drives, tape drives etc. It controls all I/O devices, keeps
 track of I/O request, issues command to these devices.
 4. File management: Data is stored in a computer system as files. The file management
 module of the as would manage files held on various storage devices and transfer of files
 from one device to another. This module takes care of creation, organization, storage,
 naming, sharing, backup and protection of different files.
 5.Scheduling: The as also establishes and enforces process priority. That is, it determines
 and maintains the order in which the jobs are to be executed by the computer system. This
 is so because the most important job must be executed first followed by less important jobs.
 6.Security management: This module of the OS ensures data security and integrity. That is,
 it protects data and program from destruction and unauthorized access. It keeps different
 programs and data which are executing concurrently in the memory in such a manner that
 they do not interfere with each other.
 7. Processor management: as assigns processor to the different task that must be performed
 by the computer system. If the computer has more than one processor idle, one of the
 process waiting to be executed is assigned to the idle processor.

18. What are the methods used in a system for cooling?

a)    Large System Case

b)    Arrangement of Internal Components

c)    Keeping the System Clean.

d)    Proper Working of the System Case Fan.

19. What can you do with computers?

In the workplace, many people use computers to keep records, analyze data, do research, and manage projects. At home, you can use computers to find information, store pictures and music, track finances, play games, and communicate with others—and those are just a few of the possibilities.

You can also use your computer to connect to the Internet, a network that links computers around the world. Internet access is available for a monthly fee in most urban areas, and increasingly, in less populated areas. With Internet access, you can communicate with people all over the world and find a vast amount of information.

Here are some of the most popular things to do with computers:

 The web   

The World Wide Web (usually called the web, or web) is a gigantic storehouse of information. The web is the most popular part of the Internet, partly because it displays most information in a visually appealing format. Headlines, text, and pictures can be combined on a single webpage—much like a page in a magazine—along with sounds and animation. A website is a collection of interconnected webpages. The web contains millions of websites and billions of webpages.


Surfing the web means exploring it. You can find information on the web about almost any topic imaginable. For example, you can read news stories and movie reviews, check airline schedules, see street maps, get the weather forecast for your city, or research a health condition. Most companies, agencies, museums, and libraries have websites with information about their products, services, or collections. Reference sources, such as dictionaries and encyclopedias, are also widely available.


The web is also a shopper's delight. You can browse and purchase products—books, music, toys, clothing, electronics, and much more—at the websites of major retailers. You can also buy and sell used items through websites that use auction-style bidding.


E‑mail (short for electronic mail) is a convenient way to communicate with others. When you send an e‑mail message, it arrives almost instantly in the recipient's e‑mail inbox. You can send e‑mail to many people simultaneously, and you can save, print, and forward e‑mail to others. You can send almost any type of file in an e‑mail message, including documents, pictures, and music files. And with e‑mail, you don't need a postage stamp!

    Instant messaging   

Instant messaging is like having a real-time conversation with another person or a group of people. When you type and send an instant message, the message is immediately visible to all participants. Unlike e‑mail, all participants have to be online (connected to the Internet) and in front of their computers at the same time. Communicating by means of instant messaging is called chatting.

 Pictures, music, and movies   

If you have a digital camera, you can move your pictures from the camera to your computer. Then you can print them, create slide shows, or share them with others by e‑mail or by posting them on a website. You can also listen to music on your computer, either by importing music from audio CDs or by purchasing songs from a music website. Or, you can tune in to one of the thousands of radio stations that broadcast over the Internet. If your computer comes with a DVD player, you can watch movies too.


Do you like to play games? Thousands of computer games in every conceivable category are available to entertain you. Get behind the wheel of a car, battle frightening creatures in a dungeon, or control civilizations and empires! Many games allow you to compete with other players around the world through the Internet. Windows includes a variety of card games, puzzle games, and strategy games. For more information.

20. What CMOS and CMOS battery?

Short for complementary metal oxide semiconductor. Pronounced see-moss. The CMOS chip holds the date, time, and  system setup parameters. This chip is powered by a 3Volt  CMOS battery.

21. What do you mean by a processing device? What are the various types of processing devices?

The main function of a computer is to process data. The various types of processing device in a computer are;

a) Microprocessor

b) Chipset


22. What is a Web browser ?

A web browser is a software application that enables a user to display and interact
 with text, images, videos, music and other information typically located on a Web page
 at a website on the World Wide Web or a local area network.
 Important web browsers:
 • Mosaic, April 22,1993
 • Netscape Navigator and Netscape Communicators, October 13, 1994
 • Internet Explorer, August 1995
 • Opera,1996
 • Mozilla Firefox, 2004
 The most popular browser is Internet Explorer and is published by Microsoft and the
 second most popular browser is Netscape (or Netscape Navigator). It is also freely
 Under the title bar, a browser displays its main menu.

The Toolbar: 

Under the main menu, a browser is equipped with small pictures called
 buttons. Microsoft Internet Explorer usually displays these buttons on their own range
 (called a toolbar).

The Address bar :

the space where the address of a particular website is to be typed to view the site.

23. What is a cache? How it is mapped with main memory?

Cache memory: - 

The cache memory is employed in computer systems to compensate
 for the speed differential between main memory access time and processor 10gic.CPU logic
 is usually faster than main memory access time, with the result that processing speed is
 limited primarily by the speed of main memory.

 Mapping of memory:-

The basic characters tics of cache memory is its fast access time.
 Therefore, very little or no time must be wasted when searching for words in the cache. The
 transformation of data from main memory to cache memory is referred as a mapping
 process. Three types of mapping procedures are of practical interest when considering the
 organization of cache memory: Associative mapping, Direct mapping and Set-associative

24. What is a microprocessor?

The most important electronic component on the computer. It is a programmable logical device for processing data. In the world of personal computers, the termsMICROPROCESSOR and CPU are used interchangeably.

25. What is a storage device? What is the common classification?

Storage devices are used to store data in the computer. The different types of storage devices are;

a) Magnetic Devices.

b) Optical Devices.

c) Solid-State Storage Devices.

26. What is advantages and disadvantages of Internet?

 There are many advantages of using the internet such as:


 The foremost target of internet has always been the communication By the advent of
 computer’s Internet, our earth has reduced and has attained the form of a global village.
 Now we can communicate in a fraction of second with a person who is sitting in the
 other part of the world. Today, for better communication, we can avail the facilities of
 e-mail; we can chat for hours with our loved ones.


 Information is probably the biggest advantage that internet offers. The Internet is a
 virtual treasure trove of information. Any kind of information on any topic under the sun
 is available on the Internet. The search engines like Google, yahoo is at your service on
 the Internet.


 Entertainment is another popular area why many people prefer to surf the Internet.
 Downloading games, songs, movies are certain examples.


 Many services are now provided on the internet such as online banking, job seeking,
 booking railway tickets, etc.


 Ecommerce is the concept used for any type of business deals that involves the transfer
 of information across the globe via Internet. Eg. Shopping online for books, household
 goods etc.

27. What is an image scanner? Explain the two types of image scanners. Give the limitations of image scanners?

Image scanner is an input device, which translates paper documents into an electronic
 format that can be stored in a computer. The input documents can be typed text, pictures,
 graphics, or even hand written material. They are also known as optical scanners because
 optical technology is used for converting an image into electronic form.
 The two types of image scanners are flat-bed scanners and hand-held scanners.
 Flat-Bed Scanner: A flat-bed scanner consists of a box having a glass plate on its top and a
 lid that covers the glass plate. The document to be scanned is placed upside down on the
 glass plate. When the scanner is activated the light source which is situated below the glass
 plate moves horizontally from left to right. After scanning one line the light beam moves up
 a little and scans the next line. The process is repeated until the document is scanned
 Hand-Held Scanner: A hand-held scanner consists of a set of light emitting diodes encased
 in a small case that is convenient to hold in hand during operation. During scanning the

scanner is dragged slowly from one end of the document to the other with its light on.
 Dragging should be very steady over the document, otherwise the conversion into its bit map
 will not be correct. They are mostly used where high accuracy is not important and the
 volume of the scanned document is low. They are cheaper than flatbed scanners. .
 The limitations of image scanners are:.
 • Word processing cannot be done on the input documents, as the documents are stored
 as images instead of text.
 • Storing the document as an image requires lot of storage space than compared to
 storing the document as a text.

28. What is an Internet Address?

Messages are transmitted from one computer to another;
 every computer in the Internet must have a unique and specific address. An Internet or
 IP address, as it is sometimes called, consists of four numbers separated by periods.
 The smallest address would be while the biggest would be
 1234.5678.9101.1121. Only computers are expected to remember all these numbers
 without getting confused.

29. What is an operating system? Explain how throughput, turnaround time and response time areused to measure the overall performance of a computer system?

Operating system is an integrated set of programs that
 a. Controls the resources of a computer system.
 b. Provides its user an interface that is easier to use as compared to a bare machine.
 There are several possible purposes of an operating system: To provide an environment for
 a computer user to execute programs on computer hardware in a convenient and efficient
 manner. To allocate the separate resources of the computer as needed to solve the problem
 given. The allocation process should be as fair and efficient as possible.
 Throughput means number of processes completed / time unit.
 Turnaround Time is the average time elapsed from when process is submitted to when it
 has completed.
 Response Time - Average time elapsed from when process is submitted until useful output
 is obtained.

Typically, Utilization and Throughput are traded off for better Response Time. Response
 time is important for OS's that aim to be user-friendly. In general, we would like to
 optimize the average measure. In some cases, minimum and maximum values are
 optimized, e.g. it might be a good idea to minimize the maximum response time.

30. What is disadvantages and disadvantages of Internet?

 Theft of Personal information

 While using the internet, there is the danger of personal information such as name,
 address, and credit card number etc. being accessed and misused by culprits.


 Spamming refers to sending unwanted e-mails in bulk, which are useless and obstruct
 the entire system.

 Virus threat

 Virus is nothing but a program which disrupts the normal functioning of the computer
 systems. Computers attached to internet are more prone to virus attacks and they can
 end up into crashing the whole hard disk.


 This is a serious issue concerning the Internet. There are thousands of sites on the
 Internet that provide bad/obscene images/content that affect the users' mental health.

31. What is Domain Name System?

The Domain Name System (DNS) helps users to find their way around the Internet.
 Every computer on the Internet has a unique address, called the "IP address". But it is
 hard to remember everyone's IP address. The DNS makes it easier by allowing a
 familiar string of letters (the "domain name") to be used instead of the IP address. So
 instead of typing, you can type, which is easier to
 Domain names have the format: Eg. The third set of letters of an address are intended to indicate the
 type of organization hosting the computer.
 Domain name &Meaning
 COM -Commercial organizations
 GOV- Government institutions
 NET- Major Network support centers
 ORG -Organizations other than those above

Two letter codes - The final two letter codes indicate the country of origin.
 Eg:.'in' is used for India

32. What is DVD-ROM? What are the differences between CD-ROM and DVDROM?

a) DVD (also known as "Digital Versatile Disc" or "Digital Video Disc") is a popular optical
 disc storage media format used for data storage. Primarily uses are for movies, software, and
 data backup purposes, DVDs are of the same form factor as compact discs (CDs), but allow
 for 8 times the data storage capacity (single-layer, single-sided).
 i) Storage capacity: Going by the storage capacity, the DVD specifications have four disk
 configurations, ranging from 4.7 GB to 17 GB. It ranges from single-sided, single-layer
 disks that are much like traditional CD ROM disks to double-sided double-layered DVDs.
 Normally a DVD ROM with a minimum storage capacity can store up to the data of 7 CD
 ROMs. Normally the capacity of a CD ROM is only 650 MB. The capacity of DVD ROM
 starts from 4.4 GB, which is 7 times more than a normal CD ROM. However, this storage
 capacity of DVD ROM relates to single-layer storage. But with double-layer storage, the
 storage capacity of DVD ROM can go up to 8 GB, which is 12.5 times higher than a normal
 CD ROM. Furthermore, double-sided, DVD ROM drives can store 8.8 GB, 14 times greater
 than a CD ROM's capacity. Double-sided, dual-layer DVD-ROM drives store 15.9 GB, 25
 times greater than a CD ROMs capacity. To put it differently a CD ROM can hold the entire
 encyclopedia, but a DVD ROM can hold the encyclopedia, the dictionary, the thesaurus, and
 the phone number/address of everyone in whole India with still a lot of space left! With the
 storage of a DVD ROM, you can see interactive multimedia programs that use hours of fullscreen
 video to help you see movies, play games or even learn your courses.
 ii) Speed of data transfer: DVD ROM scores over the CD ROM. Going by figures the
 minimum transfer rate of CD ROM drives is 150 KB per second. However, the minimum
 transfer rate of DVD ROM drives is 11.08 MB per second. The data transfer rate of DVD
 ROM is approximately equivalent to a 92X CD ROM.
 iii) Reliability: Individually though CD ROMs are very reliable and have a long shelf life
 yet if compared to the DVD, the DVD scores over the CDs in terms of reliability. Since
 DVD ROM discs are made of plastics bonded together, the discs are more rigid than CD
 ROM discs. Though the DVDs can also catch scratch just like CDs yet the scratches in the
 DVD normally do not matter as they are usually out of focus of the laser and therefore it
 does not affect the readability of the DVDs. In case of CDs, scratches could affect the data
 and could also make it useless if the scratches destroy critical tracks. Besides scratches, other
 factors like error correction also makes DVD much better and reliable in comparison to the
 CDs. Normally, in case of the DVD, the error correction is 10 times more effective than the
 CD error correction. Moreover the CDs normally follow RS-CIRC error correction mode,
 whereas DVD have RS-PC error correction. Likewise the error correction overhead in case
 of CD ROM is very high at 34 per cent, whereas it is only 13 per cent in case of DVD drive.

33. What is Intel Atom processor?

The Intel Atom family of processors are extremely small central processing units (CPU) found mostly in ultraportable devices, such as netbooks, cell phones and tablet PCs, according to Intel. While small and light on energy use, Atom processors can handle the most common tasks, such as email and instant messaging.

34. What is Intel Pentium?

The Intel Pentium is a series of microprocessors first developed by the Intel Corporation. These types of processors have been found in many personal computers since 1993.

35. What is jumper? What is the need?

A metal bridge that closes an electrical circuit. Typically, a jumper consists of a plastic plug that fits over a pair of protruding pins. Jumpers are sometimes used to configure expansion boards. By placing a jumper plug over a different set of pins, you can change a board's parameters.

36. What is main memory in a computer?

The main memory in a computer is called Random Access Memory. It is also known as RAM. This is the part of the computer that stores operating system software, software applications and other information for the central processing unit (CPU) to have fast and direct access when needed to perform tasks.

37. What is meant by booting? Explain the basic booting process?

:During this process the computer will perform a self-diagnostic, reporting any errors it
 may encounter. Much can be learned about the state of the computer by paying close
 attention to the series of messages passing across the display during startup.
 The basic booting process has the following sequence of operations:
 1. Power-On Self Test (POST)
 2. System Initialization, CMOS and BIOS Check
 After reading in the CMOS settings the boot sequence will continue with:
 PCI Initialization - If you have a PCI bus the system will now initialize the cards on the
 Configuration Display - The BIOS now tests and displays the system configuration,
 including the status of:
 Floppy drives
 Mouse and keyboard ports
 Serial ports
 Parallel ports
 Cache memory information: common sizes for cache memory are 64 KB, 128 KB, 256
 KB, or 512 KB.

3. Loading the Disk Operating System (DOS)
 4. Configuring the System with CONFIG.SYS
 5. Running Programs at Startup with AUTOEXEC.BAT
 6. Running Windows

38. What is SATA?

Serial ATA (SATA or Serial Advanced Technology Attachment) is a  computer businterface for connecting host bus adapters to mass storage devices such as hard disk drives and optical drives. Serial ATA was designed to replace the older parallel ATA (PATA) standard (often called by the old name IDE), offering several advantages over the older interface: reduced cable size and cost (7 conductors instead of 40), native hot swapping, faster data transfer through higher signalling rates, and more efficient transfer through an (optional) I/O queuing protocol.

39. What is Search Engines?

Although the internet is highly rich with information, the information is not always
 organized in a way that a person expects. When "browsing", it is hard to get to the
 particular information one is looking for. To provide an alternative, there are some
 specialized sites that can perform the search for users, with more or less same
 accuracy. These sites are referred to as search engines. Some of the most popular of
 them are:
 Examples : Google, Yahoo, MSN, Netscape, Alta Vista Search

 Steps to do a search

  • To do a search, first access a search engine site. Eg.

  • Each one of them provides you with a convenient box in which you can type the word or sentence to search and press Enter. Eg. Types of roses

  • The results are displayed in a list.

  • You can then click each link and check it. If a link doesn't provide the type of information you are looking for, you can click Back (the shortcut to go back on most browsers is Alt + left arrow key) and click the next link in the list.
 If you still don't find what you are looking for, you can change the word or sentence that you
 typed and start searching again. You can also try another search engine site.
 Most of the search engine sites provide more services than searching the web. For
 example, both Yahoo and MSN provide free email services.

40. What is Super computer?

The fastest type of computer. Supercomputers are very expensive and are employed for specialized applications that require immense amounts of mathematical calculations. For example, weather forecasting requires a supercomputer. Other uses of supercomputers include animated graphics, fluid dynamic calculations, nuclear energy research, and petroleum exploration.

41. What is the difference between integrated and non-integrated motherboard?

In integrated motherboard all of the external ports will be present. But in case of  non-integrated motherboard only some important ports will be available instead of all. The non-integrated motherboard is an old type of motherboard which now a day's not commonly available.

42. What is the difference between multi-tasking and multi-programming?

Multiprogramming is a method of running several different programs in a computer
 apparently at the same time.
 Usually on a mainframe - the computer has a number of programs loaded into memory and
 the operating system switches quickly between them, processing a little bit of each one in
 turn. The high speed of the processor makes it seem like more than one program is being run
 at the same time.
 Multi-tasking: Two or more programs actually run at the same time. Windows 95 and OS/2
 support multitasking. Windows 3.1 supports "task switching" but not multi-tasking.
 Extended memory is divided up into "virtual machines" that share time on a single
 processor. With multi-tasking, a computer could be receiving communication via modem in
 the background while running Excel in the foreground.

43. What is Upgrading the memory?

Adding a memory module to the existing bank on the available slot or replacing the previous one with the increased memory size is also called upgrading memory. This will surely increase the performance of the computer.

44. What types of softwares are used for specific application? Explain any one example?

Application softwares are used and developed for the specific area of application of the
 user. These are customer oriented softwares suitable for specific area of application.
 Example: Business Application
 Micro electronic technology is enabling offices to function more efficiently nowadays, by
 various concerns:
 a. In business forecasting.
 b. To keep records up-to-date.
 c. To carry out automatic checks on the stock of a particular item.
 d. To prepare pay bills and personnel records.
 e. In accounting, invoicing and billing.
 f. In banking operations and data storage.
 g. In business correspondence and communications.
 h. In functions of various types in Life Insurance Business.
 i. As an aid to management etc.

45. Why do we call motherboard a motherboard?

Motherboard is the basic integrated board of the computer on which all other components are connected. So that usually we call motherboard a "motherboard".

46. Write a note on capabilities and limitations of a computer?

Capabilities of a Computer:- Computers are capable of having great processing speeds,
 huge memory, accuracy and versatility. The can be put to use in various areas like:
 • For calculations in engineering and scientific research
 • In data processing jobs.
 • Commercial and financial applications
 • Office automation.
 • Robotics
 • Weather forecasting
 Limitations of a computer:
 • They need to be first programmed with specific instructions
 • They cannot decide how are to be programmed or provide their own input.
 • They can't interpret the data they generate.
 • They can't implement any decisions they suggest.
 • They can keep track of scientific data, but they can't conceive or express the ideas for
 continued research.

47. Write a note on components of motherboard?

1) Bus : -
 a. Address Bus
 b. Data Bus
 c. Control Bus
 2) Expansion slots: They serve the purpose of adding functionality to the computer.
 a. ISA : Industrial standard architecture.
 b. PCI : Peripheral component interface
 c. AGP : Accelerated Graphic port.
 3) CACHE Memory: It is a small fast memory that resides between CPU and main
 4) CMOS (Complementary Metal Oxide Semiconductor Battery )
 5) I-O Ports ( Input –Output Ports ): Serial , Parallel , USB etc.,

48. Write a note on Computer virus?

Viruses are collection of coded instructions which are self replicating. When a virus attaches
 itself to another file it infects it. They are normally inactive until infected program is run.
 They are broadly classified into three categories.
 a. Boot infectors
 b. System infectors
 c. Executable program infectors
 Boot infectors: Create bad sectors. They remain in the memory until the system is shutdown.
 System infectors It infects the hard disk or: bootable floppies which may contain system files.
 Executable program infectors: These are dangerous and devastating. They spread to
 almost any executable program attaching themselves to programming files.