What does a "crawl" refer to in video production?

In video production, a "crawl" specifically refers to text that moves horizontally across the screen, often positioned at the bottom. This technique is frequently used in news broadcasts, title sequences, and credits to convey information without interrupting the main visual content. The movement is typically slow and steady, allowing viewers ample time to read the text as it progresses across the frame.

While other options describe different elements of video production, they do not pertain to the definition of a crawl. A type of camera movement involves physical motion of the camera itself, images moving upward in the frame refers to a different technique known as a "scroll," and a zoom effect changes the viewer's perspective of the scene without involving any text or narrative conveyance. Therefore, the correct identification of a crawl as text moving across the bottom of the screen is essential for understanding its role in video production.