Long ago, if you wanted to converse with a computer you had to talk to it in the 1's and O's it understood, generally in the form of a punched card where a hole meant "1" and no hole meant "O". Before that it was even worse. You had to throw switches or plug wires into sockets in the computer to tell it what to do, an activity that took place in the vicinity of several thousand very hot vacuum tubes.

Eventually humans realised they could use the computer to help it talk to itself and they devised instructions made of 1's and O's that told the computer what was meant by such stuff as:

10 REM *P1*

20 LET A=49

30 LET B=50

40 LET C=45 hCH?

50 LET AVG = (A+B+C)/3

60 PRINT "The average is ":AVG

70 END

Piles of instructions like these came to be known as a program: piles of programs constitute software. By 1960, most computers understood programs. So did a handful of long-haired eccentrics called programmers. Another way to think of programs is this: They're the thoughts that computers have.

Decade of the Fifties

The major contribution of the decade of the fifties is the development of computer languages like FORTRAN (FORmula TRANslator) and COBOL (COmmon Business Oriented Language). But why do we need different types of languages. This is because the type of software language used affects the computer's ability to produce an outcome.

As we said before, whenever we instruct a computer to print our payroll or invoices the instructions are not given in English. A special language is used which the computer can understand. Computer experts have evolved several such languages and each language is suited for certain types of applications.

IBM developed FORTRAN, a major language. This language is used for solving engineering and scientific problems. An acronym for Formula Translator, FORTRAN is widely used today by the scientific and engineering communities.

FORTRAN is not well suited for business applications like Inventory or Financial Accounting where the data to be handled its voluminous. The need for a computer language for commercial data processing was first felt by the US Navy for monitoring supplies to their ships, U.S. Defense, one of the biggest spenders on computer R&D, developed the COBOL language for this purpose. COBOL stands for Common Business Oriented Language. Today, this language is popular all over the world in the commercial data processing environment.

Decade of the Sixties

Both FORTRAN and COBOL required a fair amount of persistence to master. Learning these languages was not very easy. In the sixties, we saw the introduction of the BASIC language. BASIC, developed by Tom Kurtz and John Kemeny of Dartmouth College, st for Beginner's All Purpose Symbolic Instruction Code.

While FORTRAN is dedicated to purely scientific and engineering applications, and COBOL is for commercial data processing, BASIC is in-between the two. It can be used for both kinds of applications. What is more important, BASIC is easy to learn. As a result it is a great favorite with computer enthusiasts all over the world. But it was not until the arrival of the small computers with large memories, in the second half of the seventies, that BASIC began to be used for purpose other than entertainment.

Decade of the Seventies and eighties

The seventies saw the arrival of "C" _ language that has since then taken the computing world by storm.

Many of the most important ideas of C stem from the considerably older, but still quite vital language BCPL, developed by Martin Richards. The influence of BCPL on C proceeded indirectly through the language B, which was written by Ken Thompson in 1970 for the first UNIX System on the PDP_7. hCH?

C was originally designed for and implemented on the UNIX operating system on the DEC PDP_11 at Bell Laboratories by Dennis Ritchie. C is not tied to any particular hardware or system, however, and it is easy to write programs that will run without change on any machine that supports C.