The term screencast compares with the related term screenshot; whereas screenshot generates a single picture of a computer screen, a screencast is essentially a movie of the changes over time that a user sees on a computer screen, enhanced with audio narration.
Screencasts can help demonstrate and teach the use of software features. Creating a screencast helps software developers show off their work. Educators may also use screencasts as another means of integrating technology into the curriculum. Students can record video and audio as they demonstrate the proper procedure to solve a problem on an interactive whiteboard.
Screencasts are useful tools for ordinary software users as well: They help filing report bugs in which the screencasts take the place of potentially unclear written explanations; they help showing others how a given task is accomplished in a specific software environment.