Generations of Computer:-
The evolution of computer started around 1940 with the first Generation of Computer and evolving ever since.
There are five generations of computers.
FIRST GENERATION (1946-1959)
The period of first generation computer was 1946-1959.
J.P.Eckert and J.W.Mauchy invented the first successful electronic computer called ENIAC, ENIAC stands for “Electronic Numeric Integrated And Calculator”.
For Examples:- ENIAC EDVAC UNIVAC IBM-701 IBM-650
It made use of vacuum tubes (controls the electric current flow) which are the only electronic component available during those days.
These computers can do the calculation in milliseconds.
They were very big in size, weight was around 30 tones.
These computers were based on vacuum tubes.
They were very costly due to big size.
It could store only a small amount of information due to the presence of magnetic drums.
With the use of vacuum tubes, it require a large cooling system.
Very less work efficiency.
Large amount of energy consumption.
SECOND GENERATION (1959-1965
The period of second-generation computer was 1959-1965.
Second generation computers replaced vacuum tubes with Transistor.
For Examples:- Honeywell 400, IBM 7094, CDC 1604, CDC 3600, UNIVAC 1108
Due to the presence of transistors, the size of electron component decreased. This resulted in reducing the size of a computer as compared to first generation computers.
Less energy consumption and not produce as much heat as the first generation.
Assembly language is used in the second generation.
Low cost than first generation computers.
Better speed, calculate data in microseconds.
A cooling system was required in this.
Constant maintenance was required.
Only used for the specific purposes.
THIRD GENERATION (1965-1971)
The period of third generation computer was 1965-1971.
These computers were based on Integrated circuits.
Here we used IC, which was invented by Robert Noyce and Jack Kilby In 1958-1959.
IC was a single component containing number of transistors.
For Examples:- PDP-8, PDP-11, ICL 2900, IBM 360, IBM 370
These computers were of low cost as compared to second-generation computers.
They were fast and reliable.
With the use of IC in the computer provides the small size of the computer.
IC not only reduce the size of the computer but it also improves the performance of the computer as compared to previous computers.
This generation of computers has big storage capacity.
Instead of using punch cards, mouse and keyboard are used for input.
Here used an operating system for better resource management and used the concept of time-sharing and multi-programming.
These computers reduce the computational time from microseconds to nanoseconds.
IC chips are difficult for the maintainance.
Air conditioning is required.
FOURTH GENERATION (1971-1980)
The period of fourth generation computer was 1971-1980.
This technology is based on Microprocessor.
A microprocessor is used in a computer for any logical and arithmetic function to be performed in any program.
Graphics User Interface (GUI) technology was exploited to offer more comfort to users.
For Examples:- IBM 4341, DEC 10, STAR 1000, PUP 11
Fastest in computation and size get reduced as compared to another generation of computer.
Heat generated is negligible (Very less).
They are small in size as compared to previous generation computers.
All types of high-level language (HLL) can be used in this type of computers.
The Microprocessor are very complex to design and fabrication.
Air conditioning is required in many cases due to the presence of ICs.
FIFTH GENERATION (1980-onwards)
The period of the fifth generation was 1980-onwards.
This generation is based on artificial intelligence (AI).
The aim of the fifth generation is to make a device which could respond to natural language input which user provides and are capable of learning and self-organization.
This generation is based on ULSI(Ultra Large Scale Integration) technology resulting in the production of microprocessor chips having ten million electronic component.
For Examples:-Desktop, Laptop, NoteBook, UltraBook, Chromebook
It is more reliable and works faster.
It is available in different sizes and unique features.
It provides computers with more user-friendly interfaces with multimedia features.
They need very low-level languages (LLL).
They may make the human brains dull and doomed.
Starting a computer or a computer-embedded device is called booting. When we switch on the power supply than the operating system load into the main memory. It keep all the application in the ready state.
The set of instructions or program that run at the starting when the computer is switched on is called BIOS or Basic Input Output System. BIOS is a firmware, i.e. a piece of software permanently programmed into the hardware.
If a system is already running but needs to be restarted, it is called rebooting. Rebooting may be required if a software or hardware has been installed or system is unusually slow or may be some another issue.
There are two types of booting −
Cold Booting − When the system is in switch OFF mode and we want to start it in switch ON mode than it is called cold booting.
Warm Booting − When the system is already running or in switch ON mode and needs to be restarted or rebooted, it is called warm booting.