Nessa has posted a summary of several of the major programming languages out there for developing websites today, an overview of each to give you a feel for them:

Working with a webhosting company I get asked all the time - which programming language is better? It's obvious that I'm more bias towards PHP, but there are other great languages out there that may be more suitable for certain people creating certain sites. I've decided to write a nutshell comparison on the most common languages, so you can decide for yourself.

Included in the list are: PHP, Perl, ASP/VBScript, JSP, Ruby, Python and straight HTML. She also mentions client-side languages briefly, but notes that they don't quite fall into the same category as the others.