Most people who own a camcorder also own a stack of tapes with hours of shaky, jarring video footage.

Photo courtesy The Tiffen Company, LLC
Steadicam operator Michael O'Shea with an Ultra Cine model Steadicam
To the typical amateur cameraman, this is an inevitable part of handheld video or film: When you move while you're shooting, the camera seems to pick up your body's every jolt and shake no matter how hard you try to keep it level.

But in professional movies and television shows you see lots of long, moving handheld shots that have no jolts and shakes at all. Cameramen achieve this remarkable effect using a device called a Steadicam. Since their introduction in 1976, Steadicams have become one of the most important tools in the filmmaking world -- they have expanded the cinematographer's palette considerably.

In this edition of HowStuffWorks, we'll find out what a Steadicam is and see how it can eliminate shaking and rolling. We'll also look at the history of Steadicams and explore how they are used in movies.