Computer is a wonder of modern science. It is a recent invention in the field of modern science. It has now become an essential part of modern civilization. It has brought about a revolutionary change in our everyday life. Any device that helps people perform mathematical calculations is called a computer. The term ‘computer’ refers to special kind of electronic machine that can perform mathematical calculations. A computer can also process large masses of information at a great speed. In a few minutes a computer can perform complex calculations. The fastest computers can solve millions of problems in a few seconds. Computer has lessened the work load of man. It has freed man from doing monotonous work. Computer plays a vital role in the field of business, education, art and research. It is also used to enjoy music and watch movies. A computer with internet connection has brought the whole world to our room. Actually modern computer was designed by Charles Babbage in the 1930s. The first electronic digital computer was completed in 6 by a team of scientists at theUniversityofPennsylvania. A computer can perform three functions. Firstly, it receives data. Secondly, it processes data and at last it emits data. The use of computer is so versatile that we can not go a single day without computer.