Learning Animated GIF files

Played around with some online animated .GIF file creator sites.  I made some neat combination/overlay images of different FF versions.  Here is one of my favorites.  Black Scribble (basic 3 card versions).  Files tend to be somewhat large, however.  3-6 MB.  Let it completely load and watch the transformation from 'Scribble w/ F' to the 'Loop' version to the 'No F'.