It is still necessary to learn HTML for basic sites and page layout but many designers and developers use more advanced languages such as Java, ASP, and PHP to make sites more dynamic. The core of these technologies is still good old HTML and usually a combination of CSS or Cascading Style Sheets to tidy up the code and layout.

At work we use ASP .NET to design all of our websites along with a content and inventory management backend that allows us to keep all of our websites update, process orders, and keep track of customers. ASP .NET uses VB or C with an object oriented structure which is usually more favorable for those with a programming background.

At home I use PHP to design all of my sites because it's open source and there are a lot of great resources available through books, forums, websites, and more. PHP has a much more open structure, but can also be used in an object oriented fashion.

I knew a few people and organizations using Java for their sites and they like it because of the great flexibility but it's supposed to be a very large beast to deal with. Once again Java is more favorable for someone with a programming background and translates well with applications design outside of the web.