A Reel is Instagram's short-form vertical video — typically a few seconds to a few minutes, often set to music or trending audio. It is the platform's answer to TikTok, and Reels are heavily promoted in dedicated tabs and interest-based feeds, which makes them the strongest organic reach format on Instagram for most accounts.
Reels matter because they are a discovery engine: they are shown widely to non-followers, so they are how accounts grow beyond their existing audience. YouTube Shorts and TikTok videos play the same role on their platforms, and the same craft principles carry across all three.
Win with a first-second hook, tight pacing, on-screen captions for sound-off viewing, and a payoff that earns a rewatch or a share. Native, on-platform video usually beats reposted horizontal clips, and a clear niche helps the algorithm decide who to show it to.