The timeline is used to control the scene objects over time.

Timeline

The top right part of the timeline shows the current editing range of the objects display. The initial and final frames values, specified in the text boxes on each side of the time ruler, are used to narrow this range.

Below the time ruler each object of the scene is represented as a separate track with the possibility to change its starting time and/or duration, add keyframes to create animated effects.

Refer to the Understanding the Timeline article for comprehensive explanation of timeline.
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