ASP - Active Server Pages - Microsoft's server-side scripting language with specific server tie-ins that let you access special features with certain specified tags.. Similar to PHP. Can be used to connect to databases to created dynamic pages.
CSS - Cascading Style Sheets is used to separate your content from formating.
Cold fusion - server-side application. Very powerful with its own language.
DHTML - Dynamic HTML, basically HTML mixed with JavaScript to manipulate the browser's DOM (Document Object Model)
Java - more of a full programming language. can be used for web apps or stand-alone apps.
*Java script - server-side scripting language. Use with HTML to manipulate the browser's DOM and make sites more interactive.
Perl - no experience.
PHP - like ASP but usually run on a Linux box. Can be used to connect to databases to created dynamic pages.
SSI - Server Side Include. PHP, ASP, as well as other language support these. You create a web page or part of a web page that can then be imported into other web pages as part of a template (via a tag specific to each language). Then, when you change the source page, it will be changed on all of the pages that have included it.
and XML* - eXtensible Markup Language - A very strict markup language that looks similar to HTML but is more powerful. You can also create your own schemas. Helps businesses/users share data by conforming to a strict definition. Allows one system to communicate and pass data effectively and efficiently to another.