Generations of Computers
What is a generation of computer?
Computers are developing over the years with greatly increased speeds, storage or memory and the power of computing. These developments are generally categorized by generations. Each generation is initiated by tremendous development in computer hardware or computer software that runs the machines.
There are five generations in computer development. These are as follows:
Generation of computer
|First generation vacuum tubes
|Second generation Transistors
|Third generation Integrated circuits
|Fourth generation Microprocessors 1970-present||Fifth generation
Five generation of computer
First Generation (1942-1959): Vacuum Tubes
The computers of first generation utilized vacuum tubes in their circuitry and for the storage of data and instructions.
Disadvantages of the First Generation Computers
- The vacuum tube was bulky caused a great heat problem and was never completely reliable.
- The vacuum tube caused a great number of breakdowns and inefficient operations.
Special features of the First Generation Computers
- Magnetic cores began to replace the vacuum tube as the principal memory device in the early machines.
- Programs were written in machine language employing combination of binary digits 1 & 0. Small doughnuts shaped cores were strung on wires within the computer.
Second Generation (1959-1965): Transistors
The computers of second generation utilized the transistors by replacing the vacuum tubes. A transistor is nothing but a switch that has no money parts.
Special features of the Second Generation Computers
- Programs were written in both machine and symbolic language.
- Symbolic language is also known as assembly language. These computers were reliable compact in size and virtually free of heat problems.
- Second generation computers were able to perform a single operation in micro seconds and were capable of storing terms of thousands of characters.
Third Generation (1965-1970): Integrated Circuits
The third generation computers were characterized by integrated circuits with components so that in many cases they are hardly visible to the naked eye.
Special features of the Third Generation Computers
- These computers were structured /composed of increased input/output, storage and processing capabilities.
- 1/0 devices could communicate with computers over great distances via ordinary telephone lines and could scan a page.
- They could display pictures on a television like screen could make musical sounds and could even accept limited voice input.
- Millions of characters were stored on the storage device and randomly accessed in fraction of seconds.
- These computers were able to process several programs or set of instructions simultaneously.
- Programmers were able to make use of high level problem oriented and procedure oriented language.
Fourth Generation 1970–Present : Microprocessors
The computers of fourth generation were characterized by greater input, output storage and processing capabilities. In addition to monolithic storage devices were introduced to this generation.
Special features of the Fourth Generation Computers
- Billions and trillions of characters were stored in the storage device.
- The computers could execute a program many times the size of the machine actual memory capacity, In the fourth generation, compact disk (CD) promises to become the data storage medium of choice.
- A compact disk read only memory (CD-ROM) is encoded with on and off bits.
- The average CD can store about 4800 million bit or 600 million characters of data; it is approximately a quarter of a million pages of text.
Fifth generation: artificial intelligence
The fifth generation of computers is unlike any computer existing today.
Special features of the Fifth Generation Computers
- Computers in fifth generation will be able to reason, learn, and make interfaces.
- These computers were equipped with massive primary storage capabilities and extremely fast processing speeds.
- Software will proliferate and get mush bigger and much cheaper.
- Hardware will continue to shrink in size but internal memory will increase dramatically.
- Computers will be “talking machines”.
- They will have the ability to recognize the voice and the spoken words. Expert systems software will place the knowledge of expert and consultants e.g. doctors, lowers, teachers at our disposal.
From the above discussion it can be said that the generation of computer has initiated by the developments of computers peripherals development.