"Add your URL"

I actually didn't want to start annoying you with a technical lesson in my fourth post but I think it's better to get into these technical terms rather sooner than later. I read a lot of articles and blogs on internet topics and I only understand half of them! It's not that I'm stupid (may not be an Einstein either...) or that I don't understand English (okay, my German is better...), but they're just stuffed with weird abbreviations like RSS, CSS, SaaS, SERP, SEO etc. Okay, I know that learning by doing is more effective, which is one reason why I started this blog for internet dummies. But guess what? One of the first things I had to do is "add your URL". What on earth is an URL? I thought it must be an internet address because the "http://" part was already given. So far so good, I managed that. I still want to give you the technical input because I really wonder how many of you out there really know for what URL stands for?

It stands for Uniform Resource Locator... This is about how much I understand from the Wikipedia entry.
Is there anybody out there who can give me a more simple explanation? I'd be very grateful :)
Dania