Clientside Scripting Language
Internet Explorer has support for client-side VBScript, but nobody really uses it. Javascript is an implementation of ECMAScript, by Brendan Eich at Netscape. It became the de-facto standard.
However, most languages have libraries written that can traverse an html document in the server side. In Python a common one is called Beautiful Soup.
Is Javascript the only language that can utilise the DOM API? Is there a DOM wrapper for Python?