What is Javascript?

A popular scripting language that is widely supported in Web browsers and other Web tools. It adds interactive functions to HTML pages, which are otherwise static, since HTML is a display language, not a programming language. JavaScript is easier to use than Java, but not as powerful and deals mainly with the elements on the Web page. On the client, JavaScript is maintained as source code embedded into an HTML page. On the server, it is compiled into bytecode (intermediate language), similar to Java programs.

JavaScript evolved from Netscape's LiveScript language. First released with Navigator 2.0, it was made more compatible with Java. JavaScript does not have the programming overhead of Java, but can be used in conjunction with it. For example, a JavaScript script could be used to display a data entry form and validate the input, while a Java applet or Java servlet more thoroughly processes the information. JavaScript is also used to tie Java applets together.