The first computers were tools used for mathematical calculations and astronomy. Some consider the Roman abacus as the first version of the modern day computer. The abacus was invented to help with arithmetic and dates back to 2400 BC. The Antikythera mechanism is considered to be the first analog-computing device. This machine was invented to calculate the positions of stars, constellations, and planets.
- Charles Babbage is the considered to the "father of the computer"
- Babbage was the first person to invent a computer that could be programmed.
- The computer that he invented used punch cards to compute.
- All the parts to this original computer had to be hand made so soon after its invention the British government discontinued is monetary support.
- Sir William Thomson created the first modern day version of the analog computer in 1872.
In 1938, the United States Navy created a computer that was small enough they could use it aboard a submarine. This computer was different from its predecessors in that it was electromechanical. Konrad Zuse, a German engineer, developed the first electromechanical programmable digital computer called the Z3.
During WWII, the British used an encryption machine to break German code using Colossus, which was the first electronic digital programmable computer. This computer used vacuum tubes and paper tape to perform specific operations. The US quickly followed suit and built their own electronic programmable computer named ENIAC, which was faster than Colossus. In 1948, Baby, the first stored-program computer was invented.
Other important inventions that led to the modern day computer were the transistor and the integrated circuit. The bipolar transistor replaced the vacuum tubes that were used in early computers. Transistors were smaller, cooler, more reliable, required less power to run, and lasted longer. The development of the integrated circuit led to the development of the microprocessor, the Intel 4004 was the first single-chip microprocessor. This ushered in the use of smaller computers that could be used for personal use.