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Computer Technology
What is Computer
History of Computer
Generation of computer
          First Generation 1945 - 1955
          Second Generation 1955 - 1965
          Third Generation 1965 - 1975
          Fourth Generation 1975 - 1989
          Fiveth Generation 1989 to present
Classification of computers
          On the basis of function
                       Analog Computer
                       Digital Computer
                       Hybrid Computer (Analog + Digital)
          On the basis of size
                        Mainframe computer
                        Mini Computer
                        Micro Computer or Personal Computer 
                                     Desktops
                                     Laptops
                                     Notebooks
                                     Personal Digital Assistants
                                     Tablet Computer
                        Supercomputers
Characteristics of computers
            Speed
            Accuracy
            Reliable
            Storage Capacity
            Versatile
            Automation
            Diligent
Character Representation (ASCII, ISCII, Unicode)
           ASCII (American standard code for information interchange)
           ISCII (Indian standard code for information interchange)
           Unicode
Computer Hararare 
            Primary Memory / Main Memory
            Output
            Control unit (CU)
            Arithmetic Logical Unit (ALU)
            Secondary Storage
Memory Unit / Storage Devices
             Primary Memory
                       Random Access Memory (RAM)
                       Read only Memory (ROM)
                       Cache Memory
             Secondary Storage (Auxiliary Memory)
                        Magnetic Tape
                        Magnetic Disk
                        Floppy Disk
                        Optical Disk
                        Compact Disk / Read only Memory (CD-ROM)
Computer Input Devices
            Key Board
            Bar Code Reader
            Scanner
            Mouse
            Light pen
            Speech input devices
            Optical Character Recognition
            Magnetic Ink Character Recognition (MICR)
            Optical Mark Recognition (OMR)
Computer Output Devices
             Display Screen
             Plotter
            Sound Cards and Speakers
            Printer
                     Computer system printer two type
                                      Impact Printer
                                      Non-Impact printer
                     Use printer six type
                                     Dot Matrix Printer 
                                    Ink Jet Printer 
                                    Timbal Printer.-> Type writter 
                                    Laser Printer 
                                    Thermal Transfer Printer 
                                    Thermal works transfer printer
                                                                                                                                                                       

                           Computer Technology                    

Character Representation (ASCII, ISCII, Unicode); Computer Hardware, Softwosie, Storage Devices, Input and output Devices. 


  What is Computer                                                                               


 Computer is an electronic device, which accepts data, processes it and outputs the results in the form of reports. Original objective of computer was to make fast calculation, but the modern computers besides performing fast calculations can store large volume of data, process and retrieve data as and when desired. Hence computers are also known as data processors. 

 The term computer is derived from "compute" which means "to calculate" We are all familiar with calculations in our day-to-day life. We apply mathematical operations like addition, subtraction, multiplication etc. and many other formulated  for calculations. Simple calculations take less time. But complex calculations take much longer time. Another factors is accuracy in calculations. So man explored with the idea to develop a machine, which can perform this type of arithmetic calculation faster and with full accuracy. This gave birth to a machine called "computers". 




   History of Computer                                                                          


Derices have been used to aid computation for thousands of years. The abacus was initially used for arithmetic tasks. The ancient Greek-designed Antikythera mechanism, dating between 150 and 100 BC, is the world's oldest analog computer. 

 Charles Babbage, an English mechanical engineer and Polynath, originated the concept of a programmable computer. Considered the "father of the computer" he conceptualized and invented the first mechanical computer in the early 19th century.  

During the first half of the 20th century, many scientific computing needs were met by increasingly sophisticated  analog computers, which used a direct mechanical or electrical model of the problem as a basis for computation, However, these were not programmable and generally lacked the versatility and accuracy of modem digital computers. The first modern analog computer was a tide-predicting machine, invented by Sir William Thomson in 1872. 

 By 1938, the United States Navy had developed an electromechanical analog computer small enough to use aboard a submarine. This was the torpedo Data computer, which used trigonometry to solve the problem of firing a torpedo at a moving target. During world war - II similar devices were developed in other countries as well. 

 Electronic numerical integrator and computer (ENIAC) was the first electornic  programmable computer built in the US. Although the ENIAC was similar to the colossus, it was much faster, more flexible, and it was turing - complate. Like the colossus, a "program" on the ENIAC was defined by the states of its patch cables and switches, a far cry from the stored program electronic machines that come later. Built under the direction of John mauchly and J. Presper Eckert at the university of pennsylvania, ENIAC's development and construction lasted from 1943 to full operation at the end of 1945. 

 The UNIVACI (Universal Automatic Computer 1) was the first commercial computer produced in the united states in 1951.It was designed principally by J. Presper Eckert and John Mauchly, the inventors of the ENIAC. UNIVAC was also first general-purpose electronic digital computer. 




  Generation of computer                                                                     


        Generation                                 period
First Generation                            1945 - 1955
Second Generation                        1955 - 1965
Third Generation                           1965 - 1975
Fourth Generation                         1975 - 1989
Fiveth Generation                          1989 to present



 i. First Generation 1940-1956 (16 year) 


 • Vacuum tubes : The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous taking up entire rooms. They were very expensive, to operate and in addition to using a great deal of electricity generated a lot of heat, which was often the cause of malfunctions. 

 • Machine language : First generation computers relied on machine language to perform operations and they could only solve one problem at a time. Input was based on punched cards and paper tape and output was displayed on printouts. 

 • The UNNAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC was the first commercial computer delivered to a business client. It was used in the 1951 US Bureau census. 



 ii. Second Generation 1956-1963 (7 year) 


 • Transistors : Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not sce widespread use in computers until the late 50s. The transistors was a vast improvement over the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy efficient and more reliable than their first generation processors. Second generation computers still relied on punched cards for imput and printouts for output 

 • Asembly language : Second generation computers moved from cryptic binary. machine language to symbolic or assembly languages, which allowed programmers to specify instruction in words. High level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. 

 • Magnetic Care : These were also the first computers that stored their instructions in their memory, which moved from a magnatic drum to magnetic care technology. • The first computers of this generation were developed for the atomic energy industry.  



iii. Third Generation 1964-1971 (7 year) 


 • Integrated  Circuits : The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. 

 • Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. 

 • Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their processors. 



iv. Fourth Generation  1971- Present 


 • Microprocessors : The microprocessors brought the fourth generation of computers, as thousands of integrated circuits were built ondo a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. 

 • In 1981 IBM introduced its first computer  for the home user, and in 1984 Apple introduced the Macintosh. • Microprocessors also moved out of the realm of desktop computers and into many areas of life as more and more every day products began to use microprocessors.

• As these small computers become more powerfull, they could be linked together to form networks, which eventually led to the development of the internet. 

 • Fourth generation computers also saw the development of  GUIs the mouse and handheld devices. 



 v. Fifth Generation - Present and Beyond 


 • Artificial Intelligence : Fifth generation computing devices. based on artificial intelligence are sill in development, though there are some applications, such a voice recognition, that are being used today. 

 • The use of parallel processing and superconductors is helping to make artificial intelligence a reality. 

 • Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come.

 • The goal of fifth generation computing is to develop devices that respond to natural language imput and the are capable of learning and self-organisation. 





  Classification of computers                                                                


i. function basis       ii. Size basis 



  On the basis of function :                                                              

 

According to functionality, computers are classified as :  

  i. Analog Computer :  


An analog computer (Spelt analogue in British English) is a form of computer that uses continuous physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved. 


 ii. Digital Computer : 


A computer that performs calculations and logical operations with quantities represented as digits, usually in the binary number system, 


 iii. Hybrid Computer (Analog + Digital) : 


A combination of computers those are capable of imputting and outputting in both digital and analog signals. A hybrid computer system setup offers a cost effective method of performing complex simulations, 


  On the basis of size :                                                                      


On the basis of size computers are classified as :  

i. Mainframe computer: 


A very large and expensive computer capable of supporting hundreds, or even thousands, of users simultaneously. In the hierarchy that starts with a simple microprocessor ( in watches, for example) at the bottom and moves to supercomputers at the top, mainframes are just below supercomputers. In some ways, mainframes are more powerful than super computers because they support more simultaneous programe. But supercomputers can execute a single  program faster than a mainframe. 


 ii. Mini Computer : 


In size and power mini computer lie between workstations and mainframes. In the past decade, the distinction between large minicomputers and small mainframe has blurred, however, as has the distinction between small minicomputers and workstation. But in general, a minicomputer is a multiprocessing system capable of supporting from 4 to about 200 users simultaneously. 


 iii. Micro Computer or Personal Computer 



 a. Desktops : 


A desktops is intended to be used on a single location. The spare part of a desktop computers are readily available at relatively lower costs. Power consumption is not as critical as that in laptops. Desktops are widely popular for daily use in the workplace and house holds. 


 b. laptops : 


Similar in operation to desktop, laptop computers are miniaturized and optimized for mobile use. Laptop run on a single battery or an external adapter that charger the computer batteries. They are enabled with an inbuilt keyboard, touch pad acting as a mouse and a liquid crystal display. Their portability and capacity to operate on battery power have proven to be of great help to mobile users.
 

 c. Notebooks : 


they fall in the category of laptops, but are inexpensive and relatively smaller in size. They had a smaller feature set and lesser capacities in comparison to regular laptops, at the time they came into the market. But with passing time, notebooks too began featuring almost everything that notebooks had. By the end of 2008 notebooks had began to overlake notebooks in terms of market share and sales. 


 d. Personal Digital Assistants : 


It is a hand held computer and popularly known as  a palmtop. It has a touch screen and a memory card for storage of data. PDA can also be used as portable audio players, web browsers and smart phones. Most of them can access the internet by means of bluetooth or wifi communication 

 e. Tablet Computer : 


Tablet are mobile computers that are very handy to use. They use the the touch screen technology; tablets come with an onscreen keyboard or use a  stylus or a digital pen. Apple's  iPad redefined the class of tablet computers. 


iv. Supercomputers : 


The highly calculation intensive tasks can be effectively performed by means of supercomputers. Quantum physics, mechanics, weather forecasting, molecular theory are best studied by means of supercomputers. Their ability of parallel processing and their well-designed memory hierarchy give the supercomputers, large transaction processing powers Ex. PARAM developed in India. 





 Characteristics of computers                                                               


 The characteristics which make computer make indispensable are :  

   i. Speed :   


The computer is able to process the data and gives the output in fractions of seconds, such that required information is given to the user on time enabling the user to take right decisions on right time. A powerful computer is capable of executing about 3 million calculation per second. 


 ii. Accuracy : 


The accuracy of computers is consistently high enough which avoids any errors. If it all there are errors, they are due to errors in instructions given by the programmer. 


 iii. Reliable : 


The output generated by the. computer is very reliable, but it is reliable only when the data, which is passing, as input to the computer and the program, which gives instruction are correct and reliable. 


 iv. Storage Capacity : 


The computer has a provision to store large volumes of data in the small devices, which have capacity  to store huge amounts of data and help the retrieval of data an easy task. 


 v. Versatile : 


Computers are very versatile machines. computers are capable of performing almost any task provided the task can be reduced to a services of logical step. 


vi. Automation : 


Once the instruction fed into computer it works automatically without any human intervention until the completion of execution of program or meets logical instructions to terminate the job. 


 vii. Diligent : 


A computer is free from tiredness, lack of concentration, fatigue etc. It can work for hours without creating any error. If millions of calculations are to be performed, a computer will perform every calculation with the same accuracy. Due to this capability it overpowers human being in routine type of work.




  Character Representation (ASCII, ISCII, Unicode)                         


 A computer can handle numeric and non numeric data like letters, punctuation marks and other special character. Some predefined codes are used to represent numeric and non numeric character. Some of the standard ar -  

 i. ASCII (American standard code for information interchange) 

 ii. ISCII (Indian standard code for information interchange)  

iii. Unicode 




 i. ASCII 


 American standard code for information interchange maker is name Bob Bener. ASCll is the most common format for text filers in computers and on the internet. In an ASCll file, each alphabetic, numeric, or special character is represented with a 7 bit binary number (a string of seven Os On 1s). 128 possible characters are defined. 

 Standard ASCll characters (0-127) and 
 extended ASCll characters (128-255). 
 ASCII - 7 can represent 128 character. Out of 7 bits, 3 are zone bits and 4 are numeric bits. 
 ASCll - 8 can represent 256 character. it is on extended from of ASCII - 7, 8 bit character. 






 ii. ISCIl 


 Indian script code for information interchange is a coding  scheme for representing various writing systems of India. It encodes the main indic scripts and a roman transliteration. The supported scripts are : Assamese, Bengali (Bangla), Devanagari, Gujarati. Gurmukhi, Kannada, Malayalam, Oriya Tamil, and Telugu.  

• A lot of efforts have gone into facilitating the use of Indian languages on computer. 

 • In 1991, the bureau of Indian standards adopted the ISCII. It is an 8 bit code which allows English and Indian scripts alphabets to be used simultaneously. 

 • Character coded in ISCII need 8 bits for each. 






 UNICODE 


 • Unicode is new universal code standard adopted by all new platforms. 

 • It is promoted by unicode consortium which is a non profit organization. 

 • Unicode provide a unique number of every character irrespective of the platforms, program and the language. 

 • It is a character coding system designed to support the worldwide interchange, processing and display of the written text of the diverse language. 






  Computer Hararare                                                                            


 Computer hardware consists of the components  that can be physically handled. It refers to the physical units or machine of functional units, which makes up the computer configuration which is done to suit the goals and objectives of the user. The function of these components is typically divided into three main categories input, output, and storage. Components in these categories connect to microprocessors, specifically, the computer's central processing unit (CPU), the electronic  circuity that provides the computational ability and control of the computer, via wires or circuitry called a bus. Hardware may be classified into central processing units (CPU) and the peripherals. The CPU entails control unit (CU). Arithonetic and Logic unit (ALU) and the Internal Memory unit (IMU) or main memory. The peripherals consist of the input, output and Auxiliary storage units. Input: This its the process of entering data and program in to the computer system. Therefore, the input unit takes data from us to the computer in an organized manner for processing through an input device such as keyboard mouse, MICR, OCR. etc. 

 i. Primary Memory / Main Memory : 


It is also known as internal memory. It is very fast in operation. It is used to store data and instructions. Data has to be fed into the system before the actua processing starts. It contains a part of the operating system software, one on more, execution programs being executed, the data being processed and required by the programs for execution, and processed data awaiting output.  


ii. Output : 


This is the process of producing results from the date for gething useful information, similarly the output produced by the computer after processing must also be kept some where inside the computer before being given to you in human readable form through the screen or priter. Again the output is also stored inside the computer for further processing. 


 iii. Control unit (CU) : 


The next component of computer is the control unit, which arts like the supervisor seeing that things are  done in proper fashion. Control unit is responsible for co-ordinating various  operations using time signal. The control unit determines the sequence in which computer programe and instruction are executed. Things like processing of programs stored in the main memory, interpretation of the instructions and issuing of signals for other units of the computer to execute them. It also acts as a switch board operator when several users access the computer simultaneously. Thereby, it coordinators the activities of computer's peripheral equipment as they perform the input and output. 


 iv. Arithmetic Logical Unit (ALU) : 


After you enter data through the input device it is stored in the primary storage. The actual processing of the data and instruction and performed by arithmetic logical unit. The major operations performed by the ALU are addition, subtraction, multiplication, division, logic and comparison. Data is transferred to ALU from storage unit when required. After processing the output is returned back to storage unit for further processing or getting stored. 


 v. Secondary Storage : 


It is also known as auxiliary memory. It is closely listed with the main memory. Since main memory can't be flooded with unwanted data at particular moment, same is stored in auxiliary memory from which desired data is fed to main memory as and when required by it. Thus secondary storage is used to hold mass of information  i.e. System Software, Application Programme, Cinemas, games and data files. Obviously the capacity of secondary storage is very high compared to main memory . Auxiliary  memory usually in the form of magnetic disk, magnetic tape, CD's, memory card, pen drives etc.





  Memory Unit / Storage Devices                                                         


 Memory means storage of data and the program. In computer's memory both data and programs are stored in the binary form. The binary system has only two values 0 and 1. These are called bits. 

 As human beings we all understand decimal system but the computer can only understand binary system. It is because a large number of integrated circuits  inside the computer can be considered as switches, which can be made ON or OFF. If a switch is ON it is considered I and if it is OFF it is O. 

 A bit is an acronym for bimary digit, which stands for one binary piece of information. This can be either 0 on 1. Memory unit is made up of several small storage location is called cells. Each of these cells can store a f ixed number of bits called word length. 

 Memory Sizes (capacity) : The size of memory is termed in terms B, KB, MB, GB, TB etc. 
 1 Byte            = 8 bits 
 1024 Byte      = 1 Kilo Byte (KB) 
 1024 KB        = 1 Mega Byte (MB) 
 1024 MB       = 1 Giga Byte (GB) 
 1024 GB        = 1 Tera Byte (TB) 
 1024TB.        = 1 Pets Byte (PB) 
 1024 PB        = 1 Exa Byte (EB)  
1024 EB         = 1 Zetta Byte (ZB) 
 1024 ZB        = 1 Yotta Byte (YB) 


 i. Primary Memory : 


Primary memory also known as internal memory or main memory. As soon as the computer is switched off, the contents of the primary memory is lost. You can store and retrieve data much faster with primary memory compared to secondary memory. Primary memory is more expensive than secondary memory. 

 The primary memory itself is implemented by two type of memory technologies. The first is called Random Access Memory (RAM) and other is Read Only Memory (ROM). A more appropriate name for RAM is RWM (Read Write Memory), the CPU can write and read information from any primary memory location implemented using RAM. The other part of primary memary is implemented using ROM which stands for Read Only Memory. 


 a. Random Access Memory (RAM) : 


The primary storage is referred to as Random Access Memory (RAM) because it is possible to randomly select and use any location of the memory directly to store and retrieve data. It takes same time to any address of the memory as the first address. It is also called read/write memory. 


 b. Read only Memory (ROM) : 


There is another memory in computer, which is called Read Only Memory (ROM). Again it is the ICs inside the PC that form the ROM. The storage  of program and data in the ROM in permanent.  The ROM stores some standard processing programs supplied by the manufacturers to operate the personal computer. The ROM can only be read by the CPU but it cannot be changed. 


 Cache Memory : 


Cache is a piece of very fast memory made from high speed static RAM that reduces the access time of the data. It is very expensive generally incorporated in the processor, where valuable data and progran segments are kept. Main reason for introducing cache in between main memory and processor is to compensate the speed mismatch. 


 ii. Secondary Storage (Auxiliary Memory) : 


You are now clear that the operating speed of primary memory or main memory should be as fast as passible to cope up with the CPU speed. These high speed storage  device are very expensive and hence the cast per bit of storage is also very high.  Again the storage capacity of the main memory is also very limited. 

 Often it is necessary to store hundreds of millions of bytes of data for the CPU to process. Therefore, additional memory is required in all the computer systeams. This memory is called  auxiliary memory or secondary storage. 

 Most widely used secondary storage devices are magnetic tapes, magnetic disks and floppy disks, compact disks and pen drives etc. 


 a. Magnetic Tape : 


Magnetic tapes are used for large computers like mainframe computers where large volume of data is stored for a longer time. In PCs also you can use tapes in the form of cassettes. The cost of storing data in tapes in inexpensive. 


 b. Magnetic Disk : 


You might have seen the gramophone record, which is circular  like a disk and coated with magnetic material. Magnetic disks used in computer are made on the same principle. It rotates with very high speed inside the disk drive. 


 c. Floppy Disk : 


It is similar to magnetic disk discussed above. It is 3.5 inch in diameter. The capacity of a 3.5 inch f loppy is 1.44 mega bydes. It is cheaper than any other storage devices and is portable. The floppy is a low cost device particularly suitable for personal computer system. 


d. Optical Disk : 


With every application and software there is greater demand for memory capacity. It is the necessity to store large volume of data that has led to the development of optical disk storage medium. 

 Compact Disk / Read only Memory (CD-ROM) : 


CD ROM disks are made of reflective matals. CD-ROM is written during the process of manufacturing by high power laser beam. Here the storage density is very high storage cost is very low and access time is relatively fast. 


 f loppy Disk 
 Compact Disk 
 CD 
 DVD 
 Pen Drives 
 Magnetic Tapes 
 Magnetic Disk (Gramophone Record)






 Computer Input Devices                                                                      


 Input unit consists of external devices that is, components outside the computer's CPU. It provides or fetches information and instruction to the computer. These include keyboard, mouse, light pen joystick, scanner, microphones, Optical Character Reader (OCR), Magnetic Ink Character Reader Recognition (MICR), bar code reader, badge reader, digitizer, touch screen and optical mark reader (OMR) 

 i. Key Board : 


The keyboard is very much like a standard typewriter keyboard with a few additional keys. The basic QWERTY layout of characters is maintained to make it easy for the trained typist to use the system. The additional keys are included to perform certain special functions such as loading a program, edition a text etc. Thes are known as function keys that vary in number from system to system. 


 ii. Bar Code Reader : 


These devices are generally available in super markets, bookshops, etc. Bar-code readers are photo - electric scanners that read the bar codes or vertical zebra striped marks printed on product containers. Supermarkets use a bar code system called the Universal Product Code (UPC). The bar code identifies the product to the supermarkets computer which has a description and the latest price of the product. 


 iii. Scanner : 


Scanner is an imput device that can read text or illustrations printed on paper and translate the information into a form that the computer can use. A scanner works by digitizing an image dividing it into a grid of boxes and representing cash box with either a zero or a one depending on whether the box is filled in two type scanner CCD scanner and LASER scanner.  


iv. Mouse : 


Mouse its a device that controls the movement of the cursor on pointer on a display screen. It is a small object you can roll along a hard and flat surface. As you move the mouse, the pointer on the display screen moves in the same direction 


 v. Light pen : 


Light pen is an input device that utilizes a light sensitive detector to select objects on a display screen. 


 vi. Speech input devices : 


Speech or voice input devices convert a person's speech into digital form. These input devices, when combined with appropriate software,  form voice recognition systems. These system enable users to operate microcomputers using voice commands. 


 vii. Optical Character Recognition : 


Often abbreviated as OCR, optical character recognition involves reading text from paper and translating the images into a from that the computer can manipulate. An OCR system enables you to take a book or a magazine article and feed it directly into an electronic computer file. 


 viii. Magnetic Ink Character Recognition (MICR) : 


An MICR can identify character  printed with a special ink that contains  particles of magnetic material. This device particularly finds applications in banking industry. Since the MICR system can recognise only certain character styles, the characterss have to be accurately formed. 


ix. Optical Mark Recognition (OMR) : 


Optical mark recognition also called mark sense reader is a technology where an OMR device sense the presence or absence of a mark, such as pencil mark.






  Computer Output Devices                                                                  


 Output devices receive information from the CPU and present it to the user in the desired form. Output devices include display screen, loudspeakers, printers, plotters, etc. 

 i. Display Screen : 


when a program is keyed in the screen (which is similar to a television screen) displays the characters. The user can read the program line by line and make correction before it is stored or printed on a printer. 


 ii. Plotter : 


Plotter is a device that draws pictures on paper based on commands from a computer. Plotters differ from printers in that they draw lines using a pen. As a result, they can produce continuous lines, whereas printers can only simulate lines by printing a closely spaced series of dots. Three Type f lat bid, Drum, pintch roller. 


 iii. Sound Cards and Speakers : 


An expansion board that enables a computer to manipulate and output, sounds. Sound cards are necessary for nearly all CD-ROM and have become commonplace on modern personal computers. Sound cards enable the computer to output sound through speakers connected to the board, to record sound input from a micro-phone connected to the computer and manipulate sound stored on a disk. 


 iv.Printer : 


Printer is device that prints text or illustrations on paper and in many cases on transparencies and other media. There are many different typers of printer. In terms of the technology utilized, printer fall into the following categories. 

 Computer system printer two type  


a. Impact Printer 

 b. Non-Impact printer. 


 Use printer six type -   


i. Dot Matrix Printer 

 ii. Ink Jet Printer 

 iii. Timbal Printer.-> Type writter 

 iv. Laser Printer 

 v. Thermal Transfer Printer 

 vi. Thermal works transfer printer.





















                                                                     Notes                                                                









                                                                     Question                                                           

1. Besides the computer what are the other mediums of storing information?
A. Audiovisuals                       B. Floppies 
C. CD-ROMs and Disks          D. All the above 
Ans: 

2. Match the following: 
            List A                                                 List B
1. Sound documents                          a. Combining images and sound 
2. Audio-visual documents               b. Laser video-disc use for movies
3. Digital Videodisc                          c. Allows users to copy information from a CD-ROM disc
4. CD- PROM                                   d. Sound records, sound taps
                                                          e. Optical Digital Data Disc 
A. 1-d, 2-a, 3-b, 4-c                    B. 1-a, 2-b, 3-c, 4-d 
C. 1-b, 2-c, 3-d, 4-a                    D. 1-c, 2-d, 3-a, 4-b 
Ans 

3. Match the following : 
      List-A                                                         List-B 
a. Audio-visual                                      1. computer based communication library system 
b. Verbal                                                2. film scripts communication 
c. Tele- communication                         3. television  
d. Mass-Media of communication         4. encyclopedias 
Code: 
    (a) (b) (c) (d) 
A. 2 4 1 3 
B. 2 1 4 3 
C. 2 3 1 4 
D. 3 2 1 4
Ans: 

4. Assertion (A): Electrocopying means the conversion of machine readable materials into printed materials form using document image processing and OCR technology. 
Reason (R): It is violation of copyright to convert without prior permission items owned by third parties into machine readable form and to store them on a database. 
Codes: 
A. Both (A) and (R) are true 
B. Both (A) and (R) are false 
C. (A) is false, but (R) is true 
D. (A) is true, but (R) is false
Ans: 

5.What does mnemonics mean? 
A. Aid to memory            B. Alphabetical device 
C. Empty digit                 D. None of these
Ans: 

6. The general image file formats are : 
i. TIFF                   ii. JPEG 
iii. MPEG             iv. PNG 
Codes : 
A. (i), (ii) and (iii) are correct 
B. (i), (iii) and (iv) are correct 
C. (i), (ii) and (iv) are correct 
D. (ii), (iii) and (iv) are correct
Ans: 

7. The process of configuring the disks into tracks and sectors is called 
A. Booting                  B. Formatting 
C. Labelling               D. All the above
Ans: 

8. Which was the first machine like computer ? 
A. Mark-1            B. Analytical engine 
C. Abacus            D. UNIVAC-1
Ans: 

9. Which is not the characteristic of a computer ? 
A. Handling of information                                                B. Limitless capacity 
C. More and more powerful and faster than human          D. Regularly working without direction
Ans: 

10. Who designed analytical engine? 
A. Charles Babbage               B. Pascal 
C. James watt                         D. Boyl
Ans: 

11. Which function in not related with the computer? 
A. Information retrieval                  B. Information storage 
C. Reference service                       D. Dissemination of information
Ans: 

12. The computers which get the information in the form of letters, numerals and signs are called 
A. Analog computers               B. Digital computers 
C. Hybrid computers                D. Super computers
Ans:

13. Calculating machine is developed by 
A. Shakuntala Devi                    B. Pascal 
C. Calcutta University                D. Ranganathan
Ans: 

14. Use of integrated circuits was made in 
A. First Generation Computers              B. Second Generation Computers 
C. Third Generation Computer              D. Fourth Generation Computers
Ans: 

15. When computer was applied first in India ? 
A. 1954             B. 1957 
C. 1956             D. 1961
Ans: 

16. Computer is not called as which one of the following? 
A. Artificial intelligence          B. Micro processor 
C. Data processor                    D. Data interpreter
Ans: 

17. What is the heart of micro-computers? 
A. Micro-processor            B. CPU 
C. ALU                              D. RAM
Ans: 

18. Which agency used computer first in India ? 
A. National Library Calcutta        B. INSDOC 
C. DRTC                                       D. ISI, Calcustta
Ans:

19. Transistors were used in which generation of computers? 
A. First generation                    B. Second generation 
C. Third generation                   D. None of these
Ans: 

20.Which type of computers are most suitable for use in the libraries? 
A. Analog             B. Super 
C. Digital             D. Hybrid
Ans:

21.Physical components of the computers are called as 
A. software           B. hardware 
C. humanware      D. none of these
Ans: 

22. Even though ‘Xerography’ is a photocopying method, but it is called 
A. Diazographic        B. Thermographic 
C. Electrofax             D. Electrostatic
Ans: 

23. Result obtained in computers, is called 
A. software             B. hardware 
C. output                 D. input
Ans: 

24. Identify the correct order as per increasing data storage capacity : 
A. CDROM, DVD, Cartridge, BlueRay Disc 
B. DVD, Cartridge, BlueRay Disc, CDROM 
C. Cartridge, CDROM, DVD, BlueRay Disc 
D. BlueRay Disc, DVD, Cartridge, CDROM
Ans: 

25. The major components of information technology are 
A. computer technology                                             B. communication technology 
C. reprographic and micrographic technology           D. all the above
Ans: 

26. CPU in a computer is the part of 
A. Hardware                 B. Humanware 
C. Output                      D. Software
Ans: 

27. Where does the internal memory part of computer rest in?
A. VDU                B. CPU 
C. Monitor            D. Keyboard 
Ans: 

28. What is Byte in Computers? 
A. A tool of computer            B. Language 
C. Hardware                           D. Measurement of the memory
Ans: 

29. The number of basic hardware parts in the Word Processor is 
A. 4             B. 5 
C. 6             D. 7
Ans: 

30. Transistors with integrated circuits are used in computers for their CPU in 
A. First generation computers                B. Third generation computers 
C. Fourth generation computers             D. Fifth generation computers
Ans: 

31. The second generation computers use which of their CPU 
A. Valves                  B.Vacuum tubes 
C. Transistors           D. Transistors with integrated circuits
Ans: 

32. Which of the following is first generation of computer? 
A. Super computer                B. Mini computer 
C. Micro computer                D. UNIVAC-1
Ans: 

33. RAM may be called as which of the following? 
A. Non-volatile memory       B. Volatile memory 
C. External memory              D. Internal memory
Ans: 

34. COM means 
A. Computer Output Microform                  B. Catalogue On Magnetic tape 
C. Computer Output Magnetic tape             D. Catalogue On Microform
Ans: 

35. “Lipi” is a dedicated word processor developed by 
A Tata Consultancy               B. CMC 
C. CIIL                                   D. Microsoft
Ans: 

36. DBMS stands for 
A. Data Based Mechanical System                    B. Data Based Management System 
C. Director Board of Mechanical System          D. Data Based Machine System
Ans: 

37. How many data can be stored in a CDROM? 
A. 600 MB                             B. MB 500 
C. MB 2500                           D. MB 5000
Ans: 

38. In the binary system of numbers, 100 represents the decimal number 
A. 12                B. 7 
C. 4                  D. 5
Ans: 

39. The first electronic computer called ABC was devised by 
A. Howard Read                  B. J. P. Eckert 
C. Atanasoff and Berry        D. M. Taube
Ans: 

40.  What is full form of CD-Rom? 
A. Compact Disk-Read Only Memory                    B. Compact Disk-Reading On Machine 
D. Compact Disk-Read On Memorandum              C. Compact Disk-Reading Of Material
Ans: 

41. UNIVAC-1 was built by 
A. Mauchly & Eckert                   B. Howard Read 
C. M. Taube                                  D. V. Newman
Ans: 

42. When CD-ROM was prepared and made ? 
A. 1965                      B. 1985 
C. 1977                      D. 1982
Ans: 

43. Visual Display Units (VDU) are used for 
A. Storage                             B. Output 
C. Input                                 D. Output & Input
Ans: 

44. RAM is the abbreviation of 
A. Random Access Memory           B. Read And Memory 
C. Reading Material                        D. None of these
Ans: 

45. CD-ROM is a 
A. Name of a computer                   B. Magnetic Tap 
C. Storage-Medium                         D. Programming
Ans: 

46. Which one of the following is the lowest unit of information? 
A. Bit                           B. Megabit 
C. Binary                     D. Byte
Ans: 

47. What is the function of CPU? 
A. To prepare Programmes                B. Instructions to the computer 
C. Computer language                       D. It controls all the functions of the computer
Ans: 

48. Which is not correct about CPU of a computer? 
A. It is heart of the computer                  B. It is also called processor 
C. It is brain of the computer                  D. It controls the computer
Ans: 

49. Chip technology is used in which kind of computer? 
A. Mini                       B. Micro 
C. Main frame            D. Super
Ans: 

50. In which group hardwares of computer are divided? 
A. Control unit & Peripherals            B. CPU and Memory unit 
C. CPU and Peripherals                     D. Hardware & software
Ans: 

51. How many units are there in CPU of computers? 
A. Seven                  B. Three 
C. Eight                   D. Six
Ans: 

52. What does UNIVAC stand for? 
A. Universal computer                                  B. Universal Automatic Computer 
C. Universal Arithmetic Computer               D. United Automatic Computer
Ans: 

53. Floppies are the media commonly used in 
A. Mini computers                             B. Micro computers 
C. Mainframe computers                   D. Super computers
Ans: 

54. In which year th UNIVAC-1 was developed ? 
A. 1975                     B. 1950 
C. 1951                     D. 1960
Ans: 

55. What is Hardware for a computer? 
A. Physical components                 B. Internal components 
C. Outer components                      D. Components
Ans: 

56. The Microchip was invented by 
A. INSDOC                   B. BARC 
C. IBM                          D. Intel
Ans: 

57. When the term information technology was first propounded? 
A. In the decade of 1970                      B. In the decade of 1950 
C. In the decade of 1980                      D. In the decade of 1990
Ans: 

58.  What are the popular and widely used output devices in computer? 
A. Hard disk and optical disk                   B. VDU and printer 
C. Computer disk and floppy                   D. Floppy and magnetic tape
Ans: 

59. Information technology is the science of information handling, in which, what is mainly used for processing? 
A. Library                            B. Computer
C. Information sources        D. Electronic documents
Ans: 

60. Which is component of information technology, that was used first? 
A. Storage technology        B. Communication technology 
C. Network technology      D. Computer technology
Ans: 

61. The meaning of information technology is the collection, storage, processing, dissemination and use of information. What is suitability of this definition by your opinion? 
A. It is not complete                       B. It is not suitable 
C. It is very suitable                       D. It is suitable
Ans: 

62. What do you mean by information technology? 
A. The use of technology 
B. The use of various technologies in the process of information 
C. The use of networking in the process of information 
D. The use of computer only in the process of information
Ans: 

63. Data from magnetic tape can be accessed 
A. Only randomly                             B. Only serially 
C. Both randomly and serially          D. None of the above
Ans: 

64. What are the main components of information technology? 
A. Computer technology                   B. Network technology 
C. Communication technology         D. All the above
Ans: 

65. What is full form of GUI regarding computer? 
A. Graphic Utility Interaction             B. Graphic Utility Interaction 
C. Graphical User Interface                D. Global Users Interaction
Ans: 

66. What is importance of information technology today for countries such as India? 
A. It is a tool                   B. It is a boon 
C. It is a curse                 D. It is useless
Ans: 

67. What is the main role of information technology? 
A. In handling of information               B. In storage of information 
C. In organisation of information         D. In management of information
Ans: 

68. What is becoming slowly a medium of electronic printing? 
A. Computer             B. Laser printer 
C. CD-ROM             D. Floppy
Ans: 

69. Helvetica and Times are typical names of 
A. Printers                   B. Type Machines 
C. Fonts                      D. Computers
Ans: 

70. Match the following : 
        List – I                  List – II 
a. Pen drive          i. Communication device 
b. i-Pad                ii. Web server device 
c. Wifi Modem    iii. Storage device 
d. Cloud               iv. Computing device computing 
Codes: 
       (a) (b) (c) (d) 
A. i iii ii iv 
B. iii iv i ii 
C. iv iii ii i 
D. iii ii i iv
Ans: 

71. Arrange in chronological order the following persons who were associated with computing history : 
i. J. Presper Eckart             ii. John W Mauchly 
iii. August Ada                   iv. Charles Babbage 
Codes : 
A. (iii) (ii) (i) (iv) 
B. (ii) (i) (iii) (iv) 
C. (i) (iv) (iii) (ii) 
D. (iv) (iii) (ii) (i)
Ans: 

72. How different nodes in a network are connected and how they communicate are determined? 
A By Network Connectivity         B. By Network Topology 
C. By Network Compatibility       D. None of the above
Ans: 

73.  The abbreviation MB to state the storage capacity refers to 
A. Megabytes                        B. Million bits 
C. Million bytes                    D. Megabits
Ans: 

74. The concept of Micro photography was developed by 
A. John Gutenberg                       B. Chester Cardson
C. John Benjimen Dancer           D. Ohi Battle 
Ans: 

75. The Compact Disk is conceptually referred to as 
I. Magnetic Storage 
II. Compact Storage 
III. Optical Storage 
IV. All the above 
In the type of items, there may be more than one answer. Identity the correct combination 
A. I, II and III are correct                       B. II and III are correct 
C. I and III are correct                           D. II and IV are correct
Ans: 

76. Arrange the following units of storage capacity in increasing order of magnitude. Use the code given below : 
I. Gigabyte                     II. Kilobyte 
III. Terabyte                   IV. Megabyte
Code : 
A) IV, II, III, I 
B) I, III, II, IV 
C) III, IV, I, II 
D) II, IV, I, III
Ans: 

77. Arrange the following components in order in which they were used in computers. Use the code given below : 
I. Transistors                                                  II. Vaccum Tubes 
III. Large Scale Integrated Circuit                IV. Very Large Scale Integrated Circuit 
Code : 
A. I, III, II, IV 
B. II, I, III, IV 
C. II, III, IV, I 
D. IV, I, III, II
Ans: 

78. Which one of the following is a volatile memory? 
A. RAM                        B. CD-ROM 
C. Hard Disk                 D. Floppy Disk
Ans: 

79.        List - I (Items)                    List - II (Usage) 
a. Vacuum Tube                         1. Optical Storage Device
b. Floppy Disk                           2. Used in First Generation Computers 
c. CD-ROM                               3. Used in Second Generation Computers 
d. Transistors                             4. Magnetic Storage Device 
Code : 
     (a) (b) (c) (d) 
A. 2 4 1 3 
B. 4 1 2 3 
C. 3 2 4 1 
D. 1 2 3 4 
Ans: 

80. Arrange the following chronologically according to their development : 
I. Punched Card                II. Floppy Disc 
III. Magnetic Disc            IV. Optical Disc 
A. (II) (III) (I) (IV) 
B. (I) (III) (II) (IV) 
C. (I) (II) (III) (IV) 
D. (IV) (I) (II) (III)
Ans: 

81. Select the right sequence of the following devices according to their storage capacity in descending order 
A. CD, DVD, Floppy Disc, Punched Card 
B. Floppy Disc, Punched Card, CD, DVD 
C. Punched Card, Floppy Disc, CD, DVD 
D. DVD, CD, Floppy Disc, Punched Card
Ans: 

82. Match the following 
      List- I (Medium/  Connectivity)             List- II (Type) 
a. Fax                                                       i. Optical Storage 
b. CD-ROM                                           ii. Magnetic Storage 
c. Floppy Disk                                       iii. Switching System 
d. Circuit                                                iv. Image transmission 
Code : 
     (a) (b) (c) (d) 
A. (iv) (i) (ii) (iii) 
B. (ii) (iii) (i) (iv) 
C. (i) (ii) (iii) (iv) 
D. (iii) (ii) (i) (iv)
Ans: 

83. Formatting a document in Computer means 
A. Editing the content          B. Changing the appearance 
C. Adding new content        D. Changing the font size only
Ans: 

84.  Match the following 
            List-I                                           List-II 
a. Ist generation (1946-60)                 i. Vacuum Tubes 
b. 2nd generation (1960-64)              ii. Transistors 
c. 3rd generation (1965-1970)          iii. Integrated  circuits 
d. 4th generation (1971-85)               iv. large scale IC 
Codes : 
     (a) (b) (c) (d) 
A. (i) (ii) (iii) (iv) 
B. (ii) (iii) (i) (iv) 
C. (iv) (iii) (i) (ii) 
D. (ii) (iv) (i) (iii) 
Ans: 

85. Match the following 
                   List-I                           List-II 
a. Software                              i. Key board 
b. Hardware                            ii. CD 
c. Storage Device                   iii. SOUL 
d. I/O Device                          iv. CPU 
Codes :
     (a) (b) (c) (d) 
A. (ii) (iv) (iii) (i) 
B. (ii) (iii) (iv) (i) 
C. (iii) (ii) (iv) (i) 
D. (iii) (iv) (ii) (i)
Ans: 

86. Identify the correct order of the evolution of the following storage devices 
A. DVD, Magnetic tape, Floppy, CD                    B. CD, DVD, Magnetic tape, Floppy 
C. Floppy, CD, DVD, Magnetic tape                    D. Magnetic tape, Floppy, CD, DVD
Ans: 

87. Identify the correct order of evolution of computers 
A. PC-XT, PC-AT, Main frame, Micro           B. PC-AT, PC-XT, Main frame, Micro 
C. Micro, PC-AT, PC-XT, Main frame           D. Main frame, Micro, PC-AT, PC-XT
Ans: 

88. Identify the correct order of evolution of the following storage order. 
A. Paper, Micro card, Magnetic tape, Clay tablet 
B. Clay tablet, Paper, Micro card, Magnetic tape 
C. Micro card, Magnetic tape, Clay tablet, Paper 
D. Magnetic tape, Clay tablet, Paper, Micro card
Ans: 

89. Identify the correct chronological order in which the following were established 
A. National Library of India (Kolkata), Delhi Public Library, Documentation Research and Training Centre, Raja Ram Mohan Roy Library Foundation
B. Delhi Public Library, Documentation Research and Training Centre, Raja Ram Mohan Roy Library Foundation, National Library of India (Kolkata) 
C. Documentation Research and Training Centre, Raja Ram Mohan Roy Library Foundation, National Library of India (Kolkata), Delhi Public Library 
D. Raja Ram Mohan Roy Library Foundation, National Library of India (Kolkata), Delhi Public Library, Documentation Research and Training Centre
Ans: 

90. Arrange the following in the order of computer generations : 
i. Integrated circuit                          ii. Transistor 
iii. Vacuum Tube                              iv. Chip 
Codes : 
A. (iv) (ii) (iii) (i) 
B. (iii) (ii) (iv) (i) 
C. (i) (ii) (iii) (iv) 
D. (iii) (iv) (ii) (i)
Ans: 

91.  Arrange the following according to their increasing storage capacity. 
i. CD - ROM             ii. Floppy disks                  iii. DVD 
Codes : 
     (a) (b) (c) 
A. (iii) (i) (ii) 
B. (ii) (i) (iii) 
C. (ii) (iii) (i) 
D. (i) (iii) (ii)
Ans: 

92. Match the following 
              List-I                       List-II 
  (Medium/Connectivity)      (Type)
a. Fax                            i. Optical Storage 
b. CD-ROM                 ii. Magnetic Storage 
c. Floppy Disk             iii. Switching System 
d. Circuit                      iv. Image transmission 
Codes : 
(a) (b) (c) (d) 
A. (iv) (i) (ii) (iii) 
B. (ii) (iii) (i) (iv) 
C. (i) (ii) (iii) (iv) 
D. (iii) (ii) (i) (iv)
Ans: 

93. Match the following 
                 List-I                          List-II 
a. Software                          i. Key board 
b. Hardware                        ii. CD 
c. Storage Device               iii. SOUL 
d. I/O Device                      iv. CPU 
Codes : 
      (a) (b) (c) (d) 
A. (ii) (iv) (iii) (i) 
B. (ii) (iii) (iv) (i) 
C. (iii) (ii) (iv) (i) 
D. (iii) (iv) (ii) (i)
Ans: 

94.