History And Generation of Computer

History and  Generation of computer

Abacus - It is first calculating device. They discovered the earliest form of a bead- and-wire counting machine ,which subsequently came to be known as abacus. The Chinese  improved upon the abacus so that they could count and calculate fast.

Pascal’s adding machine -  Blaise pascal , a french mathematician , invanted a machine in 1642 made up of gears which was used for adding number quickly . This machine was named as adding machine ( pascaline )and was capable of addition and substraction. It worked on clock work mechanism principle.  

Charles Babbage – He was Father of Modern computer. He designed different engine in 1833. The analytical engine was capable of performing all four arithmetic operations as well as comparison. He included the concept of central processor, storage area, memory and input-output devices in his design.   

Hollerirh’s Machine – In 1887,  Herman Hollerirh’s was his designed machine which was cape ball of recording  letters  & Numbers & Run’s from electricity which was called tabulator in 1896 Hollerirh established his our company called tabulating machine company ( T.M.C. ) The same company is today knows as international business machine corporation (I.B.M).

Generation of computer: – the term ‘computer generation’ is often used relation to the hardware of computers. Each phase of computer development is known as a separate generation of computers. Each phase of development is characterized by type of switching circuits it utilizes.   

1)                First Generation – In this generation of computer are based on vacuum tube technology.  first generation computer are weight 30 tone contained 18000vacuum tube and occupied a space of 30 feet by 50 feet. Most popular are ENAIC ( Electronic Numerical Integrator And Calculator ) ,

EDVAC ( Electronic Discrete Variable Automatic Computer ) ,

EDSAC ( Electronic Delay Storage Automatic Computer )etc.

Features:-

Ø used vacuum tube

Ø Big and clumsy computer

Ø Electricity consumption high

Ø Large air conditioners were necessary because the computers generated heat.

Ø Programming in machine language

2)              Second Generation - In second generation computer technology transistor ware placed in place of vacuum tube transistor invented by there scientist J. Bardeen. H.w. Brattain and Shockley in 1946 size of transistor 1/200^th of the vacuum tube. 

Ex-IBM 1401 , IBM 1620 , CDC 1604 ,RCA 501 .

   

Features:-

Ø Transistor replaced vacuum tube

Ø Computer became smaller

Ø Generated less heat

Ø More reliable

Ø Faster

1)                Third generation – The third generation  computers replaced transistors with ‘Integrated Circuits’ Known popularly as chips. The I.C was inverted by jack kilby at taxas instruments 1958.

Ex- IBM 360 , ICL 1900.  

        

         Features:-

Ø Integrated Circuits developed

Ø Computers smaller, faster and more reliable

Ø High-level languages appeared

2)               Forth generation – The advent of the microprocessor chip marked the beginning of the forth generation computer. Medium scale integrated (MSI) circuits yielded to large and very large scale integrated ( VLSI ) circuit packing about 50000 transistors in a chip.

              

            Features:-

Ø Integrated Circuits, smaller, faster

Ø Portable computers developed

Ø Great development in data communication

3)              Fifth generation – In this generation computing device are still in development such as voice recognition .The use of parallel processing and superconductor is helping to make artificial intelligence a reality.

                                        

       Features:-

Ø Parallel-processing

Ø Superconductors

Classification of computer

Digital Computer

The digital computer convert the data into digits (binary digits 0 and 1) and all operations are carried out on this digits at extremely fast rates. computers used for business and scientific application are digital computers

    

         Digital computer can further be classified in two ways :-

    

       (1) Purpose-wise Digital computer

                     Purpose-wise Digital computer are classified into two types

1.      Special-purpose computer is the one that is designed to perform a specific task.

2.      General-purpose computer is the one that can work on different types of input to it and thus be used in countless applications.

      (2)Size & performance wise Digital computer

                   Size & performance wise Digital computer can be classified into following types

1.      Embedded computers Computer exits in a wide range of size and power. The smallest are embedded within the circuitry of appliances washing machines , wrist watches.

2.      Microcomputers  A microcomputer is a computer whose cpu is a microprocessor. A microprocessor is a processor whose all components are on a single integrated-circuit chip . these are mainly used in offices , homes , schools , shop.

       Ex- IBM PCs, Apple Mac, IBM PS/2. 

 Three major categories at microcomputer:

a.       Programmable computer  ( PDAs ) :--Programmable computer very enormously in their computational power , speed ,memory , and physical size. The smallest of these computer can beheld in one hand and are called personal digital assistants (PDAs).

b.      Laptop  ( Notebook )  computer and desktop personal computers (PCs) :-- laptop computer and desktop pc are typically used in businesses and at home to communicate on computer networks , for word processing to track finance , and to play games.

c.       Workstations :-- workstation are similar to personal computer but the greater memory and more extensive mathematical abilities , and they are connected to other workstations or personal computer to exchange data.

1.      Minicomputer   also called mid –range servers , are more powerful computers than microcomputer in term of processing power and capabilities.

     Ex- PDP-11, VAX, 7500MANGNUM etc.

2.      Mainframe computer are designed to handle huge volume of data and information. These can support more than hundred users at same time.

     Ex-ICL 39, CDC 6600, VAX 8842, IBM 3090/600, IBM 4381.     

3.      Super computer  are the most powerful computer among digital computer. Super computer can perform billions of instructions per second, super computer have the computing capability equal to that of 40,000 micro computers. These computer cost in 15-20 million dollar range.

    Ex- CRAY X-MP-14, CDC-205, ETA GF-10, PARAM, PACE.     

Analog Computer

       In analog computers, continuous quantities are used .computations are carried out with physical quantities such as voltage, length, current, temperature etc. analog computer are mostly used in engineering and scientific applications. An electronic weight scale is an example of an analog computer.

Hybrid Computer

      Hybrid computers utilize the best qualities of both the digital and analog computers. Hybrid computers are best used in hospital where analog part is responsible for measurement of patient’s heart beat, blood pressure, temperature and other vital signs and then the operation is carried out in digital fashion to monitor patient’s vital signs.