GIF's

I am a member of a message board. The name of this board isn't important, as that's not what I'm about to discuss. What I enjoy about message boards isn't the conversations you can have with people, but rather the 2X2 avatar images people have under their names. For example, here is a personal favourite.









and another:

I never quite understood how people made them. In fact, I still don't know how people do them. However, thanks to the digital media lecture last week, I now know the difference between JPEG's and GIF's and understand that GIF's are the only format that can show animation.