premiere pro cs6

If want to put a new clip at a point in the Timeline where it will overlap with the existing clip, you have two choices:

- an Overwrite Edit, in which the portion of the new clip that overlaps the old clip will replace the contents of the old clip. Thus you might have part of a video interview with someone that you want to overwrite with some "b-roll" footage of what the person is talking about.

- an Insert Edit, in which the old clip will be split at the insertion point for the new clip and part of the old clip will be moved to the right on the Timeline to make room for the new clip. Thus you might to split up a video clip of a scene by inserting a new scene in the middle of it.

You can do Overwrite or Insert edits by moving a new clip to the same track in the Timeline as the existing clip or by putting the new clip on a new video track above the existing clip.

If you do an Insert edit on a new track, it will still split the original clip on the track below. If you do an Overwrite edit on a new track, it will not change the original clip on the track below, but you won't see that video because the new video is on a track above it.

The Overwrite edit is the default edit in Premiere, so simply drag a clip to the Timeline and Premiere will automatically overwrite the overlapping portion of the existing clip with the new clip. This will be indicated by an arrow pointing down.

To do an Insert edit, press and hold down the Command key on the Mac keyboard and then click and drag the clip to the Timeline. That will split the existing clip on the Timeline and shove the right portion further out on the Timeline to make room for the new clip. This will be indicated by an arrow pointing to the right.