Netscape Communication Corporation, in 1995 introduced Netscape Navigator 2.0 and Livescript which was later, called JavaScript. JavaScript runs on browser thus making it platform independent. it has advantages over those languages, which are compiled into machine machine code before execution. Hence it is also called Interpreted Language. JavaScript is an object-based , client side scripting language. It is an incorporation of HTML and programming language. JavaScript can also be used for server side scripting. Client side scripting means which runs on client machine and server side scripting means one that executes on a web server. It is a case sensitive language.