In the recent history, cryptography has played an important role, especially during the wartime.
The word cryptography indicates the study of secret writing and codes.
The first machine to write cryptographyc messages was created in Germany and was called Enigma. In England this invention caused the development of the Colossus series, the British electronic programmable machines. They were designed to break the top secret German Enigma code.
But before reaching these results, a long and hard work was to be done.
In America the race to develop the first computer was more exciting and adventurous since most "brains" were at work in different parts of the country at the same time. During the wartime the work of some engineers was kept under strict secrecy by the military.
There was also a legal battle to decide who was the inventor of the first digital computer. The verdict favoured John Atanasoff, the inventor of ABC. He maintained that some of his ideas were embodied in ENIAC (the Electronic Numerical Integrator And Computer), John Mauchly and Presper Eckert's computer. They never accepted the judge's decision.
The ABC was not automatic, each step had to be controlled by an operator, and it couldn't therefore be programmed.
Atanasoff had introduced four new essential ideas:
The use of electronics with vacuum tubes instead of relays;
The introduction of base-two numbers in memory and computing;
The idea of serial calculation;
The use of condensers in the memory device.
When World War II started, Atanasoff had to give up for sometime his studies. In the meantime Mauchly and Eckert began working on ENIAC for the military, but it was completed too late to be used in the battlefield.
It was a high speed 30-ton electronic monster with its 17468 vacuum tubes and 6000 switches, but it was very fast and worked. Its main job was the boring and repetitive calculation of ballistic tables, but it was also used in the scientific field for weather prediction, H-bomb calculation, and random-number studies.
ENIAC soon became famous through public demostration: it could work correctly for up to twenty hours, a record in those days, but it was difficult to program and it had virtually no memory.
It was Von Neumann, a giant in mathematics and physics, to solve the problem relating to memory. In June 1945 he produced a design of a general-purpose digital computer. It had an internal stored program, and so computing and accessing time were electronic.
The first computer based on Von Neumann's project was EDVAC (Electronic Discrete Variable Automatic Computer). It remained unchanged from 1952 to 1962. The stored-program concept made computers easier to use friendlier.