There are many different ways to convey information to learners. Videos can be very effective in e-learning as they are engaging to learners and they are especially useful for demonstrations and modelling behaviour skills. Short video clips of under 3 minutes in duration are more effective than long video segments.
Sometimes people shy away from incorporating video into courses due to the cost and time associated with recording and editing videos.
One way to develop video content is to create a whiteboard screencast.
This is an example of a screencast I developed for teachers about integrating games into the mathematics classroom.