It is a product of Netscape.
Its competitors are VBScript and Jscript, which are the products of Microsoft.
It is a scripting language.
It I case sensitive.
It provides in-built objects, which have fields and methods.
User-defined functions can be created, which can be invoked on particular event.
Java script is used with-in HTML web page using a tag <script>.
It can be used either in head or in body block, according to the need.
It is used to make the web page dynamic and for client side validation.

NOTE: With-in a script block, html tags cannot be used directly.