What is Screencasting?
screencast is a digital recording of computer screen output, also known as a video screen capture, often containing audio narration. The term screencast compares with the related term screenshot; whereas screenshot is a 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.  -Wikipedia

An Example of a Screencast Lesson

View many more screencasts on the Ecademy.