ABSTRACT
Expressions 101 The geek explanation of expressions is that it’s a JavaScriptbased programming language that allows you to manipulate time-based streams in After Effects. The artist explanation is that it’s an easy way to make any keyframeable parameter react to what another parameter is doing – such as having two layers rotate or scale together without having to copy and paste keyframes between them. Expressions are also particularly good at math, including randomizing values and automatically creating motion.
