Each platform implements it differently. TikTok reposts do not appear on your profile — they nudge the video into your mutuals' feeds. Instagram's native repost (rolled out in 2025) shares public reels and feed posts to your followers with credit, collected in a Reposts tab on your profile. X's repost is the original viral mechanic, with quote posts as the commentary variant.
For creators, reposts are a strong distribution signal — recommendation systems read them as endorsement. "Repost if" engagement framing exists for exactly that reason, straddling the line into engagement bait. Reposting your own content (to Stories, or re-publishing evergreen hits) is also standard practice for squeezing more reach from proven material.
