Microsoft AVI and ASF
Some AVI files (uncompressed or compressed with Cinepak, BMP or DV) can be played by QuickTime Player. Others may require a codec for playback. One example of an extra codec is:3ivxD4 at VersionTracker. It is free for testing purposes and handles most MPEG-4 variants including DivX 3,4 and 5, Apple MPEG-4, Philips MPEG-4 and XviD.