Part 3 – Masking and Duplicating Layers

Continue your education in Adobe After Effects CS5 by learning how to use masks to reveal different layers of your composition. Also covered is how to duplicate text from another composition so that you can reanimate in different ways.

via Classroom: Basic Compositing and Animation in After Effects | Adobe TV http://tv.adobe.com/watch/classroom-after-effects-cs5/enjoy-a-perfect-balance-of-audio/