Apple MA261Z/A User Manual - Page 117

II  Unused area: This is the area either above or below the outermost video and audio tracks in your sequence. Ordinarily, this area is blank, but if you drag clips directly into this gray area, new tracks are created to accommodate them.  Vertical scroll bars and thumb tabs: If you have more tracks than can be displayed in the Timeline window at one time, the scroll bars let you scroll through your video and audio tracks separately. The thumb tabs between the audio and video track regions can be used to define a static area that contains separate groups of audio or video tracks with their own scroll bars. This can come in handy when you have considerably more audio tracks than video. You can use the thumb tabs between your audio and video scroll bars to allocate more space to your audio tracks and less for video. For more information about creating a static area, see "Working With Tracks in the Timeline" on page 305. Horizontal Time Controls  Ruler: The ruler along the top of the Timeline represents the total duration of your edited sequence, from the first frame to the last. The ruler can be used for reference, to see the timecode corresponding to the location of clips in the Timeline. You can also click or drag the playhead in the ruler, which works exactly like the scrubber bar in the Canvas. Sequences can be a maximum of 12 hours. Playhead Ruler Chapter 9 Timeline Basics 117