Graph Editors menu > Track View – Curve Editor > Controller menu

Graph Editors menu > Track View – Dope Sheet > Controller menu

Main toolbar > Curve Editor (Open) > Track View > Controller menu

The Controller menu gives you tools for working with controllers that are assigned to objects or tracks when in the Curve Editor or Dope Sheet.

Assign—Lets you select tracks and then assign a controller to that selection. See Assign Controller.

Delete Controller—Lets you delete certain controllers, that can't otherwise be replaced (Visibility tracks, On/Off). See Delete Controller.

Keyable—Toggles the ability to be keyed of selected controller tracks. Use this with the Show Keyable button on the toolbar to see whether a track is keyable.

Copy—Puts a copy of the selected controller track into the Track View buffer. See Copy Controller.

Paste—Copies the controller track in the Track View buffer onto the selected track of another object or objects. You have the option of pasting as a copy or as an instance. See Paste Controller.

Collapse Controller— Converts procedural animation tracks to Bezier, Euler, Linear, or TCB keyframe controller tracks. Can also be used to convert any controller to these type of controllers. Allows for key reduction by using a Samples parameter. See Collapse Controller

Ignore Animation Range—Ignores the animation range for the selected controller track. When set, the track plays independently of its range and its background changes color. See Ignore Animation Range.

Respect Animation Range—Respects the animation range for the selected controller track. When set, the track plays only within its range. See Respect Animation Range.

Make Unique—Lets you turn an instanced controller into a unique controller. If a controller is instanced, making changes to it will affect where ever it is copied. If the controller is unique, then changes to it will not affect anything else. See Make Controller Unique.

Out of Range Types—Lets you extend the animation beyond the existing keyframes. Used primarily to loop and otherwise cycle your animation without having to copy keys. See Parameter Curve Out-of-Range Types.

Properties—Displays the Properties dialog, which gives access to the key interpolation types. Different controller types will offer individual options here. For example a Position XYZ controller will offer Fast, Slow, Linear, Smooth, Step, Bezier and Auto Tangent as key options, while a TCB controller will not show any of those controls. For some controllers this is the primary gateway to the animation parameters. See Properties (Track View Key Window).