What a Screencast?
"A screencast is a digital video recording that captures actions taking place on a computer desktop. Screencasts, which often contain voice-over narration, are useful for demonstrating how to use specific operating systems, software applications or website features.
Screencast production requires some kind of video-capture software and a microphone. The software, which can be a desktop client or web-based service, captures and synchronizes the video and audio files and compresses the completed movie into a format that can be shared."
Source: Margaret Rouse (2016, November). Screencast [definition]. TechTarget WhatIs.com. Retrieved from http://whatis.techtarget.com/definition/screencast