NIP-25

Reactions

NIP-25 defines reactions such as likes. A reaction is its own signed event that points at another event, which lets clients count and display responses without changing the original post.

In everyday terms, it is the open-protocol version of pressing a like button. Because it is a Nostr event, other apps can see the reaction and show it in their own way.

Read more in the official 25.md NIP document.