Edit in the Timeline track area

As you design your project, you arrange layers spatially in the Canvas and temporally in the Timeline. When you select a layer, group, or effects object in the Layers list or Timeline layers list, its timebar is selected in the Timeline track area. Drag a bar forward or backward in time, or trim it to correspond with the timing of other bars.

Motion uses the terms move, trim, slip, and split to describe the different ways of editing timebars:

As you can with objects in the Layers list, you can delete objects in the Timeline, as well as cut, copy, or paste them.

You can also modify all timebars in a group by editing the group timebar.