JavaScript was invented by Netscape as an extension to HTML. It was originally called 'LiveScript' to emphasize the real-time aspect of the programming, but that was changed quickly to 'JavaScript' when the Java language from Sun Microsystems became popular. While JavaScript bears some resemblance to Java, they are not really related. Java is a full-featured programming language that is platform independent, while JavaScript is a scripting language that does not need to be compiled.
JavaScript was introduced in the version 2 of Netscape's Navigator product, but it was rapidly extended in version 3 by Netscape to do a lot more. Navigator 3 allowed an HTML author to pre-cache images and alter them on the page when the viewer moved the mouse over various parts of the document. Navigator 4 allowed the author to alter style sheet attributes and position pieces of a document at arbitrary locations on the browser canvas. It also allowed BitStream TrueDoc fonts to be downloaded to the viewer's browser. The current version of Netscape's JavaScript is 1.2.