A screencast is a video recording of one's desktop, usually with narration. Over the summer, one of my teammates needed to know how to create a spreadsheet to view responses on a Google Form. Since we were both at home, I made a screencast to show her how to do it. I saved the screencast to my Drive, then shared it with her. So simple!
There are many applications one can use to record a screencast, but I prefer the Chrome extension Screencastify. Screencastify is a screen video recorder that allows one to record one's desktop an narrate what is occurring. I could give you the step-by-step directions of adding the extension and recording a screencast, but it is easier to show you.
Making a screencast with Screencastify
Screencastify saves directly to Google Drive, so there isn't any converting or searching for the file.
A tool for teachers and students
Screencasting is an excellent tool for teachers: it can be used to demonstrate a task and save for viewing by students (Khan Academy is probably best known for this). Teachers can use screencasts to flip elements of their classroom, create instructions and tasks for individual students, or upload to a website for students to use in the future. The neat thing about screencasts is that students are able to replay the screencast as often as needed in order to understand the task. This allows them to work more independently, and I am all for that! Here is a screencast I made for my students to show them how to add a drawing to Seesaw.
Screencasting is also an excellent way for students to record work they have done. Certain apps for iPad, like Seesaw or Explain Everything, enable students to record work as they do it. This allows students to explain what they are doing and share with others. Here is a screencast I recorded using Seesaw.
As you can see, screencasting has many uses in the classroom, and it is very easy to use!