GIF share
Embedded animated GIFs as reaction or comment. Tenor and Giphy are the dominant GIF libraries. Tenor was acquired by Google in 2018; Giphy was bought by Facebook in 2020 but forced to be sold by the UK Competition and Markets Authority in 2022.
Technically: often not even GIFs anymore — Tenor/Giphy serve MP4/WebM with a GIF fallback (smaller files, better quality). A tweet with "GIF" is typically 50 KB MP4 vs 5 MB GIF. Slack/Discord/iMessage have built-in Giphy/Tenor pickers. Custom GIFs via Photoshop, Screen-to-GIF, Kap. Twitter shut down its own GIF pipeline in 2023, reverted to Giphy embed. Classic reaction-GIF library: Michael Jackson eating popcorn, NBA-coach disbelief, Pedro Pascal cookie.