Poll: URI vs URL… Do you know the difference? Is there a difference?

So I’m here at the W3C Tech Plenary.  I just finished a session on “URI-Based Extensibility: Benefits, Deviations, Lessons-Learned.”  I’m curious how many people out there, which aren’t in a W3C working group, know the difference between URI and URL.  How many of you had heard of the acronym URI?   Post your answer in the comments.

I’d think that by throwing around terms like URI without least introducing it as a concept you’re creating another barrier to entry.