Repost on Instagram means sharing someone else's public post or reel to your own feed or story. Instagram has a built-in repost button represented by two circling arrows, allowing users to share posts and reels directly without screenshots or third-party apps. When you repost, it appears in your followers' feeds and in a special repost tab on your profile, and the original creator gets credit. You can add a comment of up to 60 characters when reposting, similar to quoting a tweet. This feature helps users share content they like and helps creators reach a wider audience.