Wednesday, September 21, 2011

Packaged software

          An application package is a generalized set of program which can be used to deal with a particular application eg. producing bill or payroll. Package tend to be available for application which are common to many users. software houses produce application packages which they can sell to a  number of customers.

Advantages of packaged software
  1.  The user saves efforts money and time for solving problems.
  2. The user will get well tried and tested programs provided by reputed software vendors. 
  3. The package are relatively fast in work and easy to access.
  4. They are user friendly.


MODEM means modulator and demodulator,In a data  communication system ,workstation and other remote input or output devices are linked with one or more processor to capture input data and receive output information . connecting equipment and software some time feferred to as interface elements are used to bridge the different operation environment of these input and output devices and processors.

Dos Tutorial

                         Every computer needs an 
operating system. Operating system 
controls all the computer equipment
and allows to check itself. DOS 
co-ordinates the computer system,
just as the conductor co-ordinate 
the orchestra. Your application 
programs run in concert with DOS, 
trusting it to keep the system humming.
DOS lets you control the things you care
about such as which program to run what 
report to print what disks to format or 
what files to erase. These functions 
share an important characteristic, the
disks and disk drives.
           There are two major types of
software They are system program which 
control the operation of the computer 
system and the application program which performs more obviously useful tasks, such as word processing , data base management spreadsheet, calculations etc. 
             The program user hardware. It must be able to receive instructions from the keybord. display and print results, read and write files from to a disk send and receive data through the computers communication connections change the colors on the color display, and so on through all the capabilities of the hardware.
             Each program doesn't have to perform all these functions for itself. A system program called the operating system manages the hardware, the operating system allows an application program to concentrate on what it does best, where it is moving paragraphs about, tracking account receivable bill or calculating stress in a bridge beam, etc. 

Introduction to QBASIC

                    QBASIC  is a programming language. Microsoft inc. has been releasing this programs development environment as a replacement for GBASIC and BASICA. The environment includes a full screen , syntax checking editor, multi-file and multi-windows editing, full debugging facilities, pull down menus and a simple yet powerful menu structure that can be driven either through the keyboard or using a mouse. Once you are in the Qbasic development environment through the keyboard or using mouse. The following basic features have enhanced the capabilities of QBASIC:
  • Subprograms allow you to separate programs into individual and logically independent modules. 
  • Structured programming supports is provided in the form of multi line IF..THEN..END type flow control structures like WHILE...WEND, SUB, FUNCTION procedures . 
  • Alphanumeric labels can be used making the programs more readable and writeable , because Qbasic does not require line numbers for its programs statements. 
  • Dynamic arrays can be declared to optimize memory usage.
  • Large numeric arrays are allowed and any number of 64 K arrays can be used and fit into available memory.
  • Metacommands allow you to control the way the compiler interprets and compilers your program.
              The Qbasic interpreter has a simple user interface and menu structure. Its design serves to aid the user in developing programs with the least number of steps. The intelligent editor checks syntax as the program line are entered. The program is compiled as it is typed allowing the program to be run in a single step. Errors are identified and reported in a convenient way that allows the user to correct them immediately.  

HTML and Web page desigining

                      The shared language of Communication of the world wide web was developed in Switzerland. This has four official languages it was difficult for people to communicate without a common language in computers. They developed a language some what similar to Esperanto ( which is combination of different languages of Europe) named Hyper Text Markup Language HTML.
         HTML allows to format text, add rules, graphics, sound and video and saved it all in a text only in ASCII file that any computer can read. The key to HTML is in the tags, the keywords enclosed in less than and greater than signs that indicates what kind of content is coming up. 
          HTML looks like a lot of text sprinkled with greater than and smaller than signs until you open the file with a special program called a browser. A browser can interpret the HTML tags and then show the formatted document on the screen. 
         The main or the key ingredient of the HTML is its Hypertext . HTML document can contain links to other HTML documents or practically anything else in the Internet. you can create several web pages and have your cursor jump from one to another as required . you can also create links to other organizations web pages giving your users access to information held at other sites.

System Development Cycle

                      The system development life cycle is classically thought of as the set of activities that analysts, designers ans users carry out to develop and implement an information system. the system development life cycle consists of the following
  • Problem definition
  • System analysis
  • System design
  • Programming analysis 
  • Program preparation band Testing
  • Implementation, Evaluation and Maintenance.
Problem defination
             To create a new system of programms or to improve or modify an existing one people have to recognize that a problem or need exists at the very beginning. 
        This problem or need may result from changing operating conditions. Managers, employees of departments  affected by changing conditions, and data processing personnel often participate in requirement sessions until the problem has been defined and specified study goals have been outlined. These goals should then be put in writing and approved by all concerned . This step cannot be by passed. 
       In this session, the requesets are clarified and then technical feasibility, economic feasibility operational feasibility study  are made., After a project request is approved its cost priority completion time and personnel requirements are estimated and used to determine where to add it any existing project list. 

System study

                  System study is derived from the Greek word systema. which means an organized relationship among the functioning units or components. In our daily life, we have come in contact with the transposition system and for over three decades, the computer system. when we talk about computer systems they are categorized in the following groups for purpose of study:
  • Physical or abstract system.
  • Open or closes system.
  • Deterministic or probabilistic systems. 
  • Man made information system. 
          We are more concerned about man made information system and we will discuss about it in the coming sections; The man made informantion system is further classified as:
  • Formal information systems
  • Informal information systems
  • Computer based information systems
            The third category of information system depends mainly on the computer for handling business applictions . system analysis develop several different types of information system to meet a variety of busuness needs . There is a class of systems collectively known as computer based information system. 
           As we have different types of transportation systems such as highway systems railwazy shstens and airlines systems  computer based information systems are of too many types. They are classified as:
  • Transaction processing system
  • Management information system
  • Decision support systems
  • Office automation systems

Language processor

                    A language processor is a special type of a computer software that has the capacity of translator the source code or program codes into machine codes. The following are different types of language processors are:
  • Compiler
  • Assembler
  • Interpreter
                  A compiler is a language processor which translate source code from high level language into binary machine code . 

     An assembler translates from a low level language to binary machine code. The assembler produces one machine instruction for each source instruction . The assemblers are generally used in assembling the source code or program code written in assembly language .
          An interpreter is different from compiler and assembler . It does not convert program into machine code format instead ot directs the CPU to obey each program statement . That means interpreter translate and executes each statement of instruction simultaneously. 
         As we discussed above, there are other language processors such as linker, debugger and loader. Let us examine how source code is compiled and it results into an executable file in c language .  

Computer Programming

                     we have already discussed about the computer programming concept in previous chapters. Before commencing the real time programming it is worthy to have revision of it's basic features. The program, which makes the computer work is called software. It is natural to think and come up with suitable step by step procedures to obtain the solution of a problem. 
         When a compter is employed to solve a problem , it must be supplied with suitable step by step procedure in a systematic sequence . These systematic notations for the specification of such of the sequence of step by step procedures in a particular programming language is referred to as a program. The tasks of developing programs for the solution of a program using computer is referred to as computer programming . The personnel engaged in the development of the program. 
        From the above description we understand that a program is a software . In the early times. programmers used to developed programs or software which were based on character user interface . In due course of time , programmers got very fantastic and graphic user interfaces and advance programming languages in which little efforts makes the things better. These software were classified in different categories . They are:
  • Application software and 
  • System software
      Application programs are basically problem oriented and they are used to solve particular type of problems . The application software is further classified as:
  • Tailored software
  • Package software
  • and Utility software

Tuesday, September 20, 2011

Fifth Generation

             The micro processors which 
extensively used as memory devices
contain very pure form of silicon 
in crystal form. Attempts are being
made by Japan, Germany and USA for 
the development of memory devices 
and main processors by using protein
or Gallium Arsenide , after the use 
of which ,it has been estimated the 
capability of computer will increase
millions of times.

Fourth Generation

             Intel corporation developed 
Intel 4004 chips in 1971for the first
time as microprocessors . The result 
of thedevelopment of IC is the development
of microprocessor .Many American 
companies started to  manufacturing 
microcomputers since 1973 . IT system
, AST , ALR,Macintosh , IBM PC Agtec
, Wang Laser , etc came into market .
Microcomputers are highly efficient in
data processing very much reliable ,
small and elegant . It ca n 
accommodate a huge number of date 
in a small place . Micro computers 
are as small as a note book and are
capable of communicating with mini 
computer s or mainframe computer s
with the help of MODEM . In the urban areas of Kathmandu valley , nearly 7/8 thousand micro computers are in used . They are used processors used in these computer s are microprocessors .
          Fourth Generations computers have micro processors which have serial numbers . The serial number indicates the capability of the computer and speed as well.

Third Generation

             Manufacture of silicon
chips was completed in late 1950s 
and in 1963. IBM company marketed 
computers containing IC as memory 
devices . IBM 360 is an example of
this type, Form the 1964 computers 
began to be connected with visual 
display unit  , high speed printer
and magnetic tapes as storage media 
or backing media. All the computer 
after 1965 contain IC in them. Third
Generation computers are still small
in size and they are much faster as they used small chips containing thousands of parts integrated in them. 
           Multiprocessing and multiprogramming are the two main advantages of this generation of computers . Actual market of computers started from the third generation computers .

Second Generation

         Noble Prize winners Jojn
Burdeen, Walter H.Brattain and 
 William B.Shockley jointly invented
transistor in 1948-1949 . Magnetic
core of transistor is more capable 
of storing information than vacuum
tube. The computer using transistor
as storage media are classified as 
second Generation computers . One 
transistor could do the task of 1000
vacuum tubes . Due to this reason, 
it seemed that smaller and faster 
computer can be replaced by 18 
transistors . IBM 1401 is an example
of this advantage. In this generation computer are relatively smaller than the First Generation computers and they are much faster and reliable . 

         Generally purpose computer was first developed by IBM . In 1950 IBM developed IBM 650, a general purpose computer. Similarly in 1951 Remington Rand developed UNIVAC-1 which could be used in business data processing . During this period. many other companies were also involved in developing computers .

First Generation

          The storage media or memory 
used in the first generation computer
was vacuum tube. Mark-1 was developed
using vacuum tubes by Howard Aiken in
1937 . Mark -1 had a length of 51 ft 
and a height 8 ft . It weighed  32 
tones. 18000 vacuum tubes were used 
and nearly 7 lakh 50 thousans parts 
were assembled in this computer .
        Nearly 500 miles long wire 
was cut into pieces to connect  
different computers . This mainframe
computer took 4.5 seconds for 
multiplications operation and 3 
additions were performed in 1 second .
Mean while EDVAC, UNIVAC-1 , MARK-11 ,
ENIAC, Z-3, Z-4 etc mainframe were manufactured. 
     Using many vacuum tubes, ENIAC( Electronic Numerical Integrator and calculator ) was devised by John Mauchly and J. Prresper Eckert jr., in 1946.
     This computer was comparatively efficient as it could perform 30 days work done by any other computer in one days at that time.From 1947 to 1955, this computer was used in American offices.   

Power Supply Devices

     The power supply device are intermediate connections between the computer and main power socket in the room. one end of these device is connected to the main supply line and the other end is connected to the computer. The following are the very common power supply devices. 
  • Volt Guard
  • Voltage Stabilizer
  • UPS 
Volt guard 
       This is the simplest device 
available in the market . This 
device goes off if the high voltage
comes. This protects from high 
voltage damage to the computer

Voltage Stabilizer 
        The automatic voltage 
stabilizer is a device that
tries to maintain the required
volt between 220 v to 240 v to 
the system. it is  also a power
supply device.

    UPS is an acronym for Uninterrupted 
Power supply. In case of the interruption
of electricity . the data may be lost or 
the work of a long time will be lost in
no time . It system , backup power supply
or diesel generator power supply system 
are kept intact all the time to prevent
the interruption of electricity in 
hospitals and sensitive places.

Magnetic Tape

        Magnetic tape is a one of the 
secondary sequential storage device
or the storage media . Magnetic tape
has also been used for years as input
storage medium and it remains a choice
today for high speed large volume 
storage . Its data density ( the 
number of characters that can be 
stored in given physical space) 
is high and its transfer rate( the 
speed with which data can be copied
into processor storage ) is 
comparatively fast.
    The tape our self nay be in a 
large reel or a small cartage or 
cassette . However packaged the
tape is usually similar to the 
kind used in tape recorder . It's
a plastic ribbon that is coated on 
one side with iron oxide or some 
other material that can be magnetised .
Tiny invisible spots representing  data 
are from the tape into main storage . The tape moves past the read head at a speed of 200 inches per second. some advantages of the Magnetic tape are given below. 
  • Magnetic tape can be reused.
  • Mass data storage in Magnetic tape is cheaper.
  • Data can be stored for long term retrieval purpose.
  • Data can be transferred directly into hard disks from Magnetic tape.   

MODEM Device

        In a data communication 
system , workstations and other 
remote input and output devices
are linked with one or more 
processors to capture input data 
and receive output information .
connecting equipment and software,
sometimes referred to as interface
elements, are used to bridge the 
different operation environments
of these input and output devices
and processor . 
   A modem is a modulation and 
demodulation devices that converts
the discrete stream of digital on 
or off electric pulses used by the
computers into the type of 
continuously variable analog wave 
patterns used to transmit the human
voice over many existing telephone 
lines. A modem is needed to modulate or convert the digital signals and the pulses whereas older telephone lines are used to transmit data.
     Actual data transfer takes place from digital to analog to digital . The data are in the binary digits atr the beginning and at the end . If the distance of such communication  increase the digital pulses may not reach the destination . 
     As a general concept, a pair of modem are require for the data communication . Each modem is connected to a computer and a telephone from keyboard is accepted by a computer and the data is transmitted to another computer via telephone line.

Hard Disk

       Hard Disk is one of the storage device in which we
can store many more things and we can store different
types of graphics design and other things, When the
floppies are kept one after another in a pile like structure
with the help ofa common spindle all the disks move with
the same speed when the spindle rotates . The cartridge
made in this principle is known as hard disk. For each
floppy , two read and write headers are connected with
the help of an arm . These arms are connected with the
header actuator motors and the spinhdle is rotated with
the help of motor.
       Generally, such types of floppies in apack or disk
pack contains 6 or 11 disks called platters. Each platter has two
surfaces so that it needs 22 read and write heads. Each head is
controlled by the circuit board. In the case of exchangeable disks the uppermost and the lowermost surfaces may come in contact with hand . Therefore these two surfaces in such disks do not contain data.
       Hard disks are commonly used in mainframe and mini computers. Obviously, in microcomputers  also. hard disks are common in use. They are also called the fixed disks. Recent development in the technology has facilitated micro computers with exchangeable hard disks.  

Monday, September 19, 2011


       Software is a general term, used to describe various program which may be used in a computer system. This is the most important concept associated with computers One you understand what a software is you will understand most of the  computers capabilities and limitation 
        A  computer is just a machine that processes information stored in the form of numbers . A computer can store data and long series of instructions which command the computers what operations to perform in the data. Such series of instruction is called a computer program .  
        Computer programs are collectively known as software. There are thousands of software available . All the software cannot be put together at the same place . For the convenience of study these software are classified into two categories They are Application software and system software.
        Application software program does specific jobs for the user such as solving equations or the producing bills results processing of campus data processing of account in the banks etc. which are provided by the computer manufacturing and supplier but inmost of the cases the software may be designed and prepared as the requirement is encountered. 


All the physical parts of the computer system like keyboard, mouse,monitor, speaker, etc is called hardware. as said earlier all computer fall under the hardware category. These component are visible and er can touch them. The cpu , printer, keyboard , monitor etc and all peripherals are known as hardware. 
   Hardware is associated with the storage and use of software such as displaying different characters on the screen storing data and information perform written in it , task print the processed data and information as result. Hardware is based on the program written in it. 
         As the electric pulses pass through component of hardware they begin to perform task as instructed by the programmer. Neither, software nor hardware can perform any task without the other . 
You can make a comparison between a computer hardware and software on the one hand and the mind and human body on the other hand . for example if you wish to purchase a ticket or you want to go here home the mind or soul. 
Similarly the physical parts of component of the computer system which we can see and touch are known as Hardware.

The Motherboard

The  Motherboard
      The motherboard is the main circuit
board or the system board in a computer is called the motherboard.
     The motherboard is a large printed circuit board thin flat sheet of plastic or sheet of fiberglass or the material with electricity pathways called traces etched  onto it . These traces connected computers that are soldered to the motherboard or attached to it  by various connectors. They connect  numerous plugsin receptacles which accommodate the computers. most important component.
   The most common component on the motherboard are follows:
  1. Buses
  2. System clock
  3. Microprocessor
  4. ROM chip
  5. sockets for RAM
  6. A CMOS Battery
  7. Expansion slot
  8. Power supply
  9. cooling fan
  10. speaker
  11. Drive etc.

Sunday, September 18, 2011

Computer system

            A computer system comprises essential components to run the computer smoothly .
The  requirement of a computer system may vary whereas the major components of a
computer system are :
  • CPU
  • Monitor
  • Keyboard
  • and printer
The power supply device is also one of the important requirement . The interconnection of input unit .
processing unit and other output unit makes a computer system.
           The common output devices are monitor and printer. Obviously, every computer is attached with
a keyboard an input devices. The volt guard is not include in computer system.but for us, it is equally important for power to these integrated components of the computer system.
  • Volt Guard
  • Central Processing Unit
  • Hard Disk
  • Keyboard
  • Main Memory
  • Monitor and Printer

Classification of computers

Mini computer

         Mini  computer  are medium in size , which means, it is bigger than
microcomputer and smaller than mainframe computer. it may require a smaller
room than that of the mainframe . The device and peripherals used in the minis
are smaller in size . It can communicate with 50 terminals . At a time at least 50
data processing programming . desktop publishing etc. Minicomputers can be
used in local area networks.
                 Minicomputers also have small general purpose system but unlike
most of the micro computer they are typically serve multiple users. They are
usually more powerful and more  expensive than minis computers.
            In physically size minicomputers  very from  desktop module to unit
of the size of small file cabines.
National computer center Nepal Telecommunication Nepal Rastra Bank ,
Agricultural Bank,RNAC, etc are using minicomputer such as Data General ,
primer, Neck, plesley, etc.

Saturday, September 17, 2011

Mainframe computer

           Mainframe computers are system that
offer faster processing speed and greater
storage capacity than a typical mini. The
whole series of mainframe models. ranging form
small to very large are usually lumped together as
a family designation by mainframes
         The space required for the installation
of these computers is about 100 sq . ft because
in peripheral devices connected to it are also large.
Most of the mainframe computers have
the following accessories. They are;
  • central processing unit
  • 4 to 8 tape units
  • 4 to 6 hard disk units
  • card readers
  • many  visual display
  • uninterrupted power supply system 
  • line printers
  • Modulators and Demodulators
  • Workstations, etc

Hybrid computers

           Hybrid computers can do the tasks of digital as well as analog computers.
The good qualities of analog and digital computers machines are sometimes
combined to create a hybrid computer or hybird computing system . In  the intensive
care unit of hospital for example, aanlog devices measure a patient heart function ,
temperature or other vital signs.
         These measurements are then converted into  numbers and supplied to a digital
component of that monitors the patients vital signs and signals a nurses station if abnormal
readings are detected. Thus, hybrid computers can transfer data from analog to digital and vice versa
Hybrid computers are used in big industries scientific research institution as well as other works. The jet
planes having computerized system for take off landing and finding its path in air are called computerized

Digital computer

          A digital computers is the one of the directly counts numbers or digits that represents
numbers letters or other special symbols. Digital computers does not  measere the distance or
does not measure how many liters of petrol is taken or what is the pressure in a compressor etc.
           Digital computers are mostly used in the preparation of reports results tabulation and graphic
representation . Thus, digital computers helps in mathematics engineering counting statistics  etc. 99% of
the computers used in  Nepal are digital computers

Analog computer

             An analog computer is the one that measure physical values such

as temperature or pressure that fall along a continuous scale or variance in temperature or pressure . For example a service station gasoline pump  contain as analog processor that converts fuel flow measurements into quantity  and price values.
       The term analog computer is derived form a greek  word analog . speedometer in cars and motor cycles is another examples of analog device. Such a change measurement device with reference to the other4 is called analog computer . The device that are used to measure the size of stone in kidney and mental disease diagnostics with the photographs are analog computers,
          Such machines are in operation in Bir Hospital Teaching Hospital and Patan Hospital . Hetauda cement factory is using a device named process control which is an analog computers. Analog computers are even less than one % in use in Nepal.

Types of computers

                   There are numerous types of plant and animals on the earth. They are
classified into different groups or phyla to study their characteristics . similarly there
are various types of computer in used . These computers are classified in to different
catogories on the basis of their capabilities and their limitations and their use.
The major classifications of computers are  as follows;
  • On the basis of work
  • On the basis of size
  • On the basis of  brand
  • On the basis of  model 
On the basis of work
  1. Analog computer
  2. Digital computer
  3. Hybrid computer

Types of computers

Thursday, September 15, 2011

Chip Development

         This may be one of the interesting things for the students to know about the
methods or procedure of development of modrn Ics are built on wafer thin slice
of extremely ofdevelopment purified silicon crystal chipsDevelopment  of a chips
is summarised in points below:

  1. The high purity polycrystalline silicon is the raw material used to manufacture                                    integrated circuit chips the heart if computer. 
  2. Under computer control the chunks are melted in a crucible and slowly drawn                                     upward forming cylinderical bulb or crystal. 
  3. The crystal is sliced into thin wafers and polished to a mirror finish. 
  4. Each chips on the wafer is then electrically tested.
  5. The wafer are then diced or cut into individual chips.

Computer Generation

            At  the end of 1950s actual test and implementation of computer started.
More and more computer were developed in search  of automatic processing and
deriving solution . The computer has reached the present stage after going through
three major modification stages. These major modification in the early mechanical
and electromechanical computers were follows.
  • Development of IC
  • Advancement on the IC in to LSI and 
  • Advancement on the VLSI
               Integrated Circuit was patented by Harwick Johnson of RCA in1953. but Robort Noyce of fairchild semiconductor and jack kilby of Texas Instrument engine are credited in developing first integrated circuit in 1959 . Later developments in the IC design resulted form.
  • the application of photo engraving to IC  manufacture  . 
  • the use of layers of silicon oxide insulation in order to build up multiple layers of crystal circuitry.  

computer in Banking system

           Computer plays vital roles in  our life. computer is needed in the many facilities among these Banking system need computer to do the several tasks and works easily and faster. computer has helped in banking system. airplane ticketing reservation system etc. In recent years the compputers are very much advance . with the help of computers your bank account can be transferred from one country to other like as japan to USA and your handprints can be dispatched through the computer system to any part of the world within a minute.

Wednesday, September 14, 2011

Computer in communication

                     Today man can communicate form one part of the world to the other part of the country easily with the help of telephone system . Within the help of computer they can solve different types of problems , sending and receiving mail or voice mail to the others in the form of text they send electronic mail. The information Technology is synonymously used as advanced applied computer technology such as in communication and networks these days . Within a minute man can communicate through telephone . Now a days many people of this whole world wants to meet the simple and easy way to do  every types of works so by the communication facilities makes the people easily.

Importance of computer

               Compute means to calculate something . To calculate  means to do some mathematical operations . About 30/40 years ago, calculator was introduced as a calculating devices . Calculator computers the number originated with a huge size and extremely high processing capabilities. Later on computers have become very powerful devices to aid the development in this field of the data processing  and computing sectors. Computer is used in almost every field in developed countries

  • computer in communications
  • computer in Banking system
  • computer in Ticketing reserving 
  • computer in Business
  • computer in Education
  • computer in Decision making 
  • computer in studies 
  • computer Education is it education
  • computer in distance education 
  • computer in Robortics
  • computer in Marketing 
  • computer in civilization
  • computer in school
  • computer in hotel manangement
  • computer in Alianve 

Development of calculation devices

              From the time of mans development they search ed for solving the problems of different calculations . They tried to find suitable devices which could do small tasks of adding subtractions multiplications and division
They developed different devices which finally led to the road way  of  the  current advanced and elegant computers.

             Abacus is a portable device that consist of beads strung on wire or wooden rods. Using an abacus one can rapidly and accurately add subtract multiply and divide large numbers and no one is sure that about exactly when the first abacus appeared . It is developed by the numbers of team of china, Egypt and Greece. It is steel used some parts of the worlds.

The slide Rule:
               In 1620 just six years  after the invention of longarithms William Oughtred  invented the slide rule. which is a calculating device the users the principles of logarithms. a simple slide rule consists of two garduated scale one of which slips upon the other it possible to obtained products quotients or their functions by inspection.
Analytical Engine:
             This is one of the world famous engine which is programmed by Ada lady augustha and designed by the charles  babbage who is known as the father and grand father of the computer science and He made the computer technology group successful in the computer history. charles babbage is one of the great professor of mathematics at cambridge university and atarted a small model of his Different engine.

History of computers

                   Computers are developed as a result of mans search for a faster way to calculate. computers are very faster because data and the instructions are repeated very fast as pulses within electronic circuits and they travel at the  speed of light  one days work on a computer would take a person more than 2700 years within a hand calculator .  People who contributed to make this possible were philosophers. inventors mathematics programmers etc. it has come  to this stage because of their tireless efforts.
                   Long before counting machines did not exit. they used  to count using their fingers or arranged stones in piles or rows. they drew lines on the ground cut  notches in stikes or tied knots in string in order to keep track of the quantities of thin gs as their need to calculate increase people sought tools to help  them.
                    Around fifth century AD Hindu philosophers developed a new method of counting form 0 to 9
this system of counting is called the decimal method .the numbers stared above 0 to 9 are the digits. Digits is a figure or toe and counting  on the  ones fingers is called the digital operation  The term digital has been extende3d to cover any  operation on distinct values which are carried out in steps.