ASP is pretty similar to PHP. I feel that once you know one it's quite easy to pick up the other.
ie, to display a server-side variable in PHP, you would do something like (correct me if I'm wrong!):$bbprodinfo[title]
ASP is considered a more professional language, since it's created by Microsoft with the focus on big business. Most big corporate websites use ASP.
Your server needs to be running Windows in order for you to install ASP, however, which is one of the reasons that many people use PHP. For the longest time Windows servers were more expensive than Linux, but lately I've noticed they are almost the same price now, depending on where you shop.