Computers Generation

Beginning

Blaise pascal made the very first attempt towards automatic computing.

He invented a device, which consisted of lots of gears and chains was

called pascaline. Later many attempts were made in this

direction.

            Charles babbage, grandfather of the modern computer.

First Generation Computers

It is indeed ironic that scientific inventions of great significance have often been linked with supporting a very sad and undesirable aspect of civilization, which is, fighting wars. Nuclear energy would not have been developed as fast, if colossal

effort were not spent towards devising nuclear bombs. Similarly, the origin of the

first truly general-purpose computer was also designed to meet the requirement of World War II. The ENIAC ushered in the era of what is known as first generations

per minute. It was, however, a monstrous installation. It used thousands of vacuum tubes (10800), weighed 30 tons, occupied a number of rooms, needed a great

amount of electricity and emitted excessive heat.

Second Generation Computers

Silicon brought the advent of the second generation computers. A two state device called a transistor was made from silicon. Transistor was cheaper, smaller and dissipated less heat than vacuum tube, but could be utilized in a similar way to

vacuum tubes. A transistor is called a solid state device as it is not created from wires, metal glass capsule and vacuum which was used in vacuum tubes. The transistors

were invented in 1947 and launched the electronic revolution in 1950.

The generations of computers are basically differentiated in technology led to greater speed, large memory capacity and smaller size in various generations. Thus, second generation computers were more advance in terms of arithmetic and logic unit and control unit powerfull. On the software front at the same time use of high level language started and the developments were made for creating better operating system and other system software.

Third Generation Computers

The third generation has the basic hardware technology: the Integrated

circuits (ICs). But what are integrated circuits? Let us first define a term called

discrete components. The discrete components such as transistors, capacitors,

resistors computer cards. All these cards/components then were put together to make

a computer. Since a computer can contain around around 10,000 of these transistors, therefore, the entire mechanism was cumbersome. The basic idea of integrated circuit was to create electronic components and later the whole CPU on a single integrated chip. This was made by the era of microelectronics (small electronics) with the invention of Integrated Circuits (ISs).

In an integrated circuit technology the components such as transistors, resistors and conductors are fabricated on a semiconductor material such as silicon. Thus, a desire circuit can be fabricated in a tiny piece of silicon. Thus, a desired circuit can be fabricated in a tiny piece of silicon. Since, the size of these components is very small in silicon, thus, hundreds  or even thousands of transistors are connected with a process of metallization, thus, creating logic circuits on the chip.

Later Generation Computers

One of the major milestones in the IC technology was the very large scale integration (VLSI) where thousands of transistors can be integrated on a single chip. Then main impact of VLSI was that, it was possible to produce a complete CPU or main memory or other similar devices on a single IC chip. This implied that mass production of architecture is sometimes referred to as fourth generation computers.

The fourth generation is also coupled with parallel computer Architectures. These computers had shared or distributed memory and specialized hardware units for floating point computation. In this era, multiprocessing operating system, compliers and special language and tools were developed for parallel processing and distributed computing. VAX9000,CRAY X-MP,IBM/3090 were some of the system developed during this era.