video format:

.avi     Audio Video Interleave File    Windows

.mov   Apple QuickTime Movie 

.mp4   MPEG-4 Video File

.mpg   MPEG Video File

.flv      Flash Video File                    any computer with Flash plugin installed

to see all format's information

links:

http://websitehelpers.com/video/

video editing:

Simple Video Editing

If you do need to edit your file or change the video or audio file formats, you can use a simple video editing tool. There are a number of shareware video editing programs available for the Macintosh and Windows for opening QuickTime or AVI files, selecting clips, and then saving them as new files with different video and audio compression formats. The simple tools are basically user interfaces that provide access to the video and audio compression and decompression codecs that are installed on your system. If you install new codecs, you then will be able to open, edit, and create files in the associated compressed format.

For Macintosh users, the Movie Player application can convert AVI files into QuickTime format. Another option for both the Macintosh and Windows is to upgrade to Apple's QuickTime "Pro" version, which provides the ability to edit files with cut and paste operations, and to save them in a variety of formats. The new QuickTime 4 Pro also supports editing and saving files in AVI and DV formats.

to learn more

Video compression:

links:

http://en.wikipedia.org/wiki/Video_compression

http://www.wave-report.com/tutorials/VC.htm

http://www.microsoft.com/windowsxp/using/moviemaker/expert/digitalvideo.mspx