Chroma Key, video tracking, and stabilizing. these are the main things required in most of the videos. You shot a video but the camera is shaking badly or you have a scene you have to replace something in your moving shot so you can use Tracking for that.

Chroma Key: Have you ever seen a Green screen behind the actors or blue screen. If you ever saw any behind the scenes of the movies than you surely have seen those colors behind actors- the technique of removing the color behind the actor is called chroma cut or chroma keying. Let's start and learn how we can do this with After effects CC.