One important family of classes is the MAXWrapper classes that give you access to the scene objects, lights, cameras, modifiers, controllers, materials, etc., in the MAX world. MAXScript essentially has its own kind of value in its own memory space that points to the MAX world object so it doesn’t interfere with the MAX world's memory; that's why they are called wrappers. But, as far as the scripter is concerned, having hold of a MAX object via MAXScript wrapper is just same as if you were pointing at it with a mouse.
Max Core Classes and Access to 3rd-Party Plug-Ins
Access to Animatable Sub-Objects
Modifier Sub-Object Transform Properties
Controller Creation and Assignment
Controller Time and Keyframe Functions
Recursive Time and Key Functions
Accessing Controller Keys and Key Properties