Computer Generations :)

 Computer:

  A computer is an electronic device that manipulates information, or data. It has the ability to store, retrieve, and process data. You can use a computer to type documents, send email, and browse the Web. You can also use it to handle spreadsheets, accounting, database management, presentations, games, and more.

 Computing:

The use or operation of computer is called computing.

 Computer Generation:

The computers of electronic age are further divided into 5 generation on the basis of technology used by the computer. The different generations are:

•                    First Generation of computers

•                    Second generation of computers

•                    Third generation of computers

•                    Fourth generation of computers

•                    Fifth generation of computers

i) First Generation of Computers

• Technology used: Vacuum tube

• Operating speed : Millisecond range

• Programming language used: Machine language

• Memory used:

•         Primary memory    : Magnetic core memory

•         Secondary memory: Magnetic drum,  Magnetic tape.

•  I/O device:

Punched card as input device, printing device as output device.

• Use: Simple mathematical calculation.

• Computers were extremely large in size, and they required special cooling system. e.g.: ENIVAC, ED VAC, UNI-VAC, etc.

ii) Second Generation of Computers:

•      Technology used: Transistor

•     Operation speed  : Micro second range (10-6 sec)

•       Programming language used: Assembly language

•       Memory used:

•           Primary memory: Magnetic core memory.

•           Secondary memory: Magnetic drum, Magnetic tape.

•     I/O  : Punched card as input device, Printer as output device

•       Use: Computers were used for complex scientific calculations.

•      The size, cost, power requirement, heat generation decreased compared to previous generation.

•      Processing speed, storage capacity, use of the computer increased compared to previous generation.

E.g.: IBM 1620, IBM 7094, LEO MARK III, etc.

Advantages of transistor over vacuum tube:

•  One transistor could replace one thousand vacuum tubes.

•   Size of a transistor is 1/200th times of a vacuum tube.

•  The power requirement of a transistor is 1/20th times of a vacuum tube.

• Transistors are more reliable than vacuum tube.

iii) Third Generation of Computers

•  Technology used: IC (Integrated Circuit)

•  Operating speed : Nanosecond range (10 -9 sec)

•  Programming language used: HLL (High Level Language)

                            Like FORTAN, COBOL, PASCAL, C, C++, etc.

•  Memory used:

•            Primary memory: Semiconductor memory (silicon)

•            Secondary memory: Magnetic tape, Magnetic disk like floppy disk, hard disk, etc)

• I/O device: Keyboard as input device, monitor as output device.

• Use: Computers were used for managing population census, bank, insurance company, etc.

• Concept of database was developed and used.

• Size, cost, power requirement, heat generation decreased compared to previous generations.

• Processing speed, storage capacity, use of the computer increased compared to previous generations.

E.g.: IBM 360 series, ICL 900 series, Honeywell 200 series, etc.

IC and its types: