Chapter 17. MEL and Expressions Primer

In Maya, many repetitive tasks can be made easier with MEL (Maya Embedded Language) or expressions. MEL is a scripting language, so if you have any experience with Perl or Javascript, MEL should seem familiar to you. MEL can be used for a wide range of tasks. The Maya interface is built out of numerous MEL scripts, allowing it to be very customizable and flexible.

Expressions are scripts, too, and they even use MEL, but they work a little differently. You can enter expressions into any node's parameters, instead of keyframing, and you can assign expressions to an object's parameters, rather than using a variable. In this way, expressions let you make connections between nodes more directly and efficiently. Expressions are usually executed at each frame in a sequence and tend to execute faster, so they're very useful for creating animation, character rigs, and particle systems.