When you upload a video to your business Facebook page a freeze frame or still capture of part of the video is selected as a thumbnail image.
This is what people see of the video before they click on it and it starts playing.
This image can have a large impact on whether someone gets engaged enough to play the video in the first place and works with the surrounding text that you use to give the video context.
Therefore being able to tweak this image is important if you are using the video to market your business. In this video Mick shows you how to do that.