History and Generation of Computers

1. In 1822, Charles Babbage conceptualized and began developing the Difference Engine, considered to be the first automatic computing machine.

2. Then after almost a decade, Charles Babbage proposed the first general mechanical computer, the Analytical Engine. The Analytical Engine contained an Arithmetic Logic Unit (ALU), basic flow control, and integrated memory concept and is the first general-purpose computer.

3. In 1946, ENIAC- Electronic Numerical Integrator and Computer was the first electronic general-purpose computer. It was the first large-scale computer to run at electronic speed without being slowed by any mechanical parts. And it was invented by J.Presper Eckert and John W. Mauchly. 

4. Douglas Engelbart invented the first computer mouse.

5. First computer with RAM - MIT introduces the Whirlwind machine, a revolutionary computer that was the first digital computer with magnetic core RAM and real-time graphics.

6. The first minicomputer - In 1960 Digital Equipment Corporation released its first of many PDP computers the PDP-1.

7. The first laptop - First Laptop was introduced in 1981 by Adom Osborne and the company “EPSON” manufactured first Laptop.

The following table categorises generations of computers and other important factors associated with the generations. 

Subject	1st generation	2nd generation	3rd generation	4th generation	5th generation
Period	1940-1956	1956-1963	1964-1971	1971-present	present & beyond
Circuitry	Vacuum tube	Transistor	Integrated chips (IC)	Microprocessor (VLSI)	ULSI (Ultra Large Scale Integration) technology
Memory Capacity	20 KB	128KB	1MB	Magnetic core memory, LSI and VLSI. High Capacity	ULSI
Processing Speed	300 IPS instructions Per sec.	300 IPS	1MIPS (1 million inst. Per sec.)	Faster than 3rd generation	Very fast
Programming Language	Machine, Language	Assembly language & early high-level languages(FORTRAN, COBOL, ALGOL)	C,C++	Higher level languages,C,C++,Java	All the Higher level languages,,Neural networks,
Example of computers	UNIVAC, EDVAC	IBM 1401, IBM 7094, CDC 3600,D UNIVAC 1108	IBM 360 series, 1900 series	Pentium series,Multimedia,	Artificial Intelligence, Robotics