B-roll
B-roll is supplementary footage cut into a video to support or illustrate the main A-roll (the speaker on camera). In short-form video, B-roll is typically 1–4 second inserts of relevant imagery, gameplay, screen recordings, or stock footage that visualize what the speaker is describing. Used well, B-roll boosts retention; used to cover the punchline, it kills replay.
The traditional film-school definition of B-roll is "everything that isn't the primary subject." In short-form video, the working definition is narrower: B-roll is the visual support that fills the screen while the speaker continues talking off-camera. It serves three functions — illustrate (show what the speaker is describing), retain (visual variety holds attention), and pace (cuts every 2–4 seconds match short-form viewer expectations).
The most common B-roll mistake in short-form is cutting away to B-roll over the closing line of a clip. Viewers read emotion from the speaker's face — when the punchline lands on a face, the clip resolves emotionally. When the punchline lands on B-roll, the viewer reads "produced content" and bounces. Land closing lines on the speaker; use B-roll for the middle.
Some AI clip generators can add B-roll for you. Clipzing.com does on its Creator and Agency plans: it finds licensed stock footage that matches what is being said, keeps it away from the opening seconds, and shows you the proposed shots before anything is rendered. Every shot can be swapped or removed.
Related terms
Jump cut
A jump cut is a video edit that removes time between two similar shots, creating a visible discontinuity in the speaker's position or framing. In short-form video, jump cuts compress speech (cutting out pauses, filler words, slow segments) to maintain the fast pacing the format demands. A well-executed jump cut every 3–5 seconds keeps retention high.
Aspect ratio
Aspect ratio is the proportional relationship between a video's width and height, expressed as width:height. The dominant short-form ratio in 2026 is 9:16 (vertical, 1080×1920) used by TikTok, Instagram Reels, and YouTube Shorts. Long-form video uses 16:9 (1920×1080). Square 1:1 is used by LinkedIn and Instagram feed.
Auto-reframe
Auto-reframe is an AI feature that converts a video from one aspect ratio to another by tracking the subject (typically the active speaker's face) across frames and re-cropping the output to keep the subject centered. The dominant use case is converting 16:9 source footage into 9:16 vertical clips for TikTok, Reels, and YouTube Shorts.
Viral hook
A viral hook is the first 1–3 seconds of a short-form video clip — the line, image, or question designed to stop the thumb-scroll and earn the next 5 seconds of attention. In 2026, hooks that lead with a specific number, a stand-alone declarative sentence, or a contradiction outperform vague openers by an order of magnitude in retention.