The third generation of computers was in the years 1965-1971 and they used the (ICs) Integrated circuits as the main internal component instead of transistors that were used in the second generation of computers. The integrated circuits were invented by Jack Kilby of Texas Instruments and Robert Noyce of Fairchild Semiconductor in 1958. Integrated circuit is a component that contains more than one transistor. It is also called a chip or microchip. Each integrated circuit consisted of resistors, transistors and capacitors. The third generation computers were reliable, smaller in size and very efficient.
In the third generation they also introduced monitors and keyboards, where the keyboard was the major component of input while the monitor served as the major component of output. They were used with an operating system that allowed the computer to run many applications within one specified time. It also had a central program that monitored the memory.
They used a higher level of language which included FORTRAN that was introduced in 1956 and ALGOL that was introduced in 1958. The languages enabled the computers to understand algebraic languages and functions, stimulation languages, procedure oriented languages, Business oriented languages and extensible languages.
The main features of the third generation computers are:
1. They were smaller in size 2. They were faster and reliable 3. They required less maintenance 4. They used the integrated circuits 5. They generated less heat compared to the previous generations of computers 6. They were cheaper 7. They used a higher level of language 8. They used the magnetic core and solid states as the main storage. 9. The output and input device were more sophisticated
There were several types of the third generation computers, these include:
1. IBM System– it was announced by the International Business Machines Corporations in the year 1964. It contained the hybrid integrated circuits that worked with in 32 bits word with a 360 assembly language. It was also used in processing lunar landings in NASA. It was very useful and valuable because its mainframe could run programs. It made a huge impact in the computer world especially in terms of work load and power.
2. UNIVAC– It was introduced in 1964 when the integrated circuits replaced the thin memory for register storage. They also had faster and smaller cores that were used in the UNIVAC 1107. In 1969 they produced an identical machine which was slower but cheaper for most of the customers and people who needed it. It did not have enough memory to be used as the UNIVAC 1108.
3. PDP (Personal Data Processor) – It was among the first mini computers to get to the market. It was sold for 20,000$ for five years but the price reduced to 5,000$ and had a memory of 4095 words. The computer was small in size, affordable and had a good speed.
5. IBM- 370-168
6. CDC 6600
7. Honeywell-6000 series
The advantages of the third generation computers were:
1. It had a good storage capacity.
2. It was less costly
3. The size was smaller making it portable
4. They generated less heat
5. It performed calculations in nanoseconds
6. Maintenance cost was low
7. It consumed less power
8. It was very reliable
The disadvantages of the third generation computers were:
1. It required air conditioning
2. It is highly sophisticated in technology therefore it is required in the manufacturing of integrated circuit chips
There are some differences between the third generation computers and the second generation computers. These include:
1. The second generation computers used transistors while the third generation computers used the integrated circuits
2. The second generation computers measured the operating speed in microseconds while the third generation computers measured the operating speed in nanoseconds
3. The second generation computers used the magnetic tapes as secondary storage while the third generation computers used the magnetic disks for secondary storage.
4. The second generation computers used a high level of programing while the third generation computers used a massive high level of language.
5. The second generation computers did not have the input and output while the third generation computers had the keyboard as the major input and the monitor as the major output component.
The third generation of computers is an upgrade of the second generation computers and it made a great impact in the computer world because the third generation computers were very fast, reliable and very accurate.