Theoretically a computer is designed to assist people perform various forms of calculations or types of secretarial or office duties. The abacus was the first form of computer which was used for basic mathematic procedures or deductions. The abacus consisted of several rows of stones which were manipulated into different positions and counted. This was the beginning of the modern electronic form for inputting information into a computer which it then processes the information and shoots out the completed calculation.
Beginning in the 1940's and into the 1950's the first electronic computers were designed by ENIAC which stands for (Electronic Numerical Integrator And Computer), these were very large and complicated, these were reprogrammable and were able to solve a vast array of computing issues. These monstrosities were designed using thousands of vacuum tubes with several other components weighed 27 tons and used 150 kilowatts of power. There were a few other similar computers during this time frame but none of them were available to the individual.
Between 1955 and 1960 the transistor was invented which began to replace the vacuum tubes. They were not as large as the earlier computer, and required a lot less power to operate. They also put out a lot less heat than the original models. In 1953 the University of Manchester created the most popular transistor computer which was the IBM 1401. In 1956 IBM produced the first disk drive which was the IBM 350 RAMAC
The microchip was invented in the 1960's opening the door for the computers that we are familiar with today. Circuits were made from a single piece of silicon, a semiconductor which allowed for a more compact and practical production. The process was a very gradual process. The first minicomputer was the bridge to the mainframe, the microcomputer appeared with the introduction of microchips into the computer industry.
This led to the development of the microprocessor and the first CPU which was the Intel 4004 which was the beginnings of the modern personal computer we are all so familiar with today. Today computers are used daily for processing images, spread sheets and different forms of data. The most significant discovery or invention was the graphical user interface and the mouse that was designed to run the machine. The inventor of this awesome product is Doug Engelbart and his people at the Stanford Research Lab. It is unfortunate that their idea didn't take hold when it was presented in 1968. It wasn't until 1973 that the invention was accepted and enhanced by the Xerox PARC research center where their researchers created the first computer which had a mouse-driven GUI with the Xerox Alto. The computer was still not accepted and again the invention was placed on hold. In 1984 thanks to Steve Jobs negotiating skills and insight he directed Apple to improve the product and it was introduced by Apple as the Macintosh which was the first mass-market computer available to the general public that included the interface and mouse. Microsoft followed a short time later with Windows and thus began the competition between these two successful companies.