iMovie is a video editing program only available on Apple. iMovie is in the iLife family of programs, with the likes of iTunes. Apple's iMovie is installed on all of the Macintosh computers in the IMAGE Lab. iMovie is designed for beginners to make digitally editing videos easy. The Macs in the IMAGE Lab are running OS9 and iMovie 2.
Please be aware that iMovie is very simple and easy to learn, but for some projects, Adobe Premiere or a more powerful program might be a better choice. Likewise, for smaller or simpler projects, iMovie is more manageable and easier to learn than a program like Premiere.
NOTE: The best way to start learning a new program is to follow the tutorial supplied by the program's makers.
Articles on using iMovie:
http://www.macaddict.com/magazine/2000_04/imov_1.html
http://www.macworld.com/2000/09/bc/04imovie/