Computer Fundamentals & Generations
A computer is an electronic machine which takes data as an input from the user process the data and gives information as an output to the user. It means it process data and gives desired output as information. It performs very fast comparing to human being. It comes in a vast of variety according to their size, work and purpose.
1. Based on Size : Micro Computer, Mainframe Computer, Mini Computer, Super Computer
2. Based on Work : Analog Computer, Digital Computer and Hybrid Computer
3. Based on Purpose: General Purpose and Special Purpose
The computer generations are classified in different years. These are following:

Ist Generation

Year: 1940-1950
Used: Vacuum Tubes
Memory: Magnetic Drums
Language: Machine Language
Performance: Very slow & expensive

IInd Generation

Year : 1950-1960
Used: Transistors
Memory: Magnetic Tape
Language: Assembly Language, High Level Language (Fortron, Cobol)
Computer: IBM 7094, UNIVAC 1107
Performance: Slightly faster & cheaper

IIIrd Generation

Year : 1960-1970
Used: Integrated Circuits (ICs), Motherboards, Operating Systems
Memory: Magnetic Core
Language: High Level Language (Basic)
Computer: NCR-395, IBM 360
Performance: Multitasking, fast, cheap

IVth Generation

Year: 1970-Present
Used: Large Scale Integrated Circuit (LSI), Microprocessor
Memory: Semi-Conductor Memory, Winchester Disk
Language: High Level Language (Pascal, C, C++, Java)
Computer: Cray1, IBM z9, Desktop, Laptop, Tablets
Performance: Fast & Cheap with GUI Interface (Windows, Macintosh, Linux)

Vth Generation

Year: Present and Future
Used: Very Large Scale Integrated Circuit (VLSI)
Memory: Hard Disk, Pen Drive
Language: High Level Language (Node.JS, Ruby, Swift, Python and Many more)
Computer: Super Computers, Artificial Intelligence, Robotics, Self Drive Cars and many more
Performance: Very Fast & Smart, Multitasking