The four generations of computers!

1st generation! 1940-56

The first generation of computers used vacuum tubes* and magnetic drums* for memory, which was limited. They were expensive to run and not many people could afford them.

2nd Generation! 1956-63

The second generation used transistors and allowed the computer to be smaller and much faster.

3rd Generation 1964-71

The integrated circuit was invented and transistors were made smaller and placed on silicone chips.

4th generation 1971- now!

We now have the microprocessor, and computers are considerably thinner, so we can fit thousands of intergrated circuits on to just one silicone chip.

*Vacuum tubes- Tube with no air!

*Magnetic drums- Direct access storage device