Canon Rebel T2i Quick Start Manual page 76

Copying Video Clips to Your Computer
The camera records video using a H.264 codec
(45- 50 mbps) in the .mov container. These
files will open up in QuickTime Player, VLC media player
or any video editing program, including iMovie.
Simply copy the clips from the SD card on to your
computer and import them into the editing software
of your choice.
There is no need to convert these files.
The .THM (thumbnail image) files can be discarded.