Software is a set of programs written in a programming language which does a specific and designated task (Somerville 2010). Computer software eventually was invented in 1940's. Computers needed a program to instruct it to do a specific task. For the same assembly language was developed which consists of small instructions written in codes. In 1950 a high level programming language which consists of English like sentences called FORTRAN was developed. FORTRAN stands for Formula Translation and it could perform scientific computations. 1960's saw the development of more programming languages like COBOL, Algol and PL/1. Along with it, operating systems to operate the computers like DOS and VMS. During development of these software the need for a proper method for software development was recognized. The first conference on software engineering was held in 1969. With the onset of a new stream of science called software engineering, many more software related to databases, structured programming languages and operating systems came into existence.

Instructions, Scientific, Development, Existence.