If you wish to create advanced, dynamic websites, or wish to utilise existing web scripts such as forums, guestbooks or content management systems you will need access to a server side scripting language.
Not all web hosting accounts support all common scripting languages, so this is an important factor in your search for the perfect web host.
The "standard" choice for server side scripting on Unix/Linux platforms is PHP. It is easy to learn and fast to program in. Java (JSP/Servlets) is often the preferred choice for bigger projects. Those who plan to become expert Windows programmers can't go wrong with ASP.net, with language choices for both beginners and more experienced programmers. ColdFusion, Perl and Python are also good programming languages with their unique strengths although are not as widely used as PHP or ASP.