Your websever can respond however it wants to a particular request. That is to say that a url path doesn't have to correspond to a filesystem path. The short answer for apache is to use mod_rewrite, but you'd get the same effect by making websites like the grown ups do: with web frameworks.
so, for every single site out there who's webpages end in no url path of .html or .php such as iam.com/newb then they are either using mod_rewrite, a web framework (which sounds like you can't code to me, what does that mean?), or by using the oldschool method of putting an index file into a directory?
>>8
You code in a web framework. Here's a simple excesize: using sockets and select in C produce a small server to service http requests. Good, now you can change the response that server gives based on whatever you want (eg cookies [=sessions], ip address, database), ie server side programming. You don't have to write your own server though, since existing servers + web frameworks will let you tie in your own code at the appropriate places.