---
title: "ActivityPub"
description: "The W3C protocol the Fediverse runs on. Every post and profile is a typed JSON-LD object with its own web address."
topic: "Structured Data & Schema"
canonical: "https://geordy.ai/glossary/structured-data/activitypub"
---
# ActivityPub

The W3C protocol the Fediverse runs on. Every post and profile is a typed JSON-LD object with its own web address.

ActivityPub is what lets Mastodon, Lemmy, PeerTube, Pixelfed and Threads talk to each other. Content is published as Activity Streams objects: typed, JSON-LD, and each one addressable at a stable URL. Anything that follows a reference to your content gets structured data with attribution attached rather than scraped HTML. Worth knowing: a server fetches your objects when something already references them, so publishing alone does not put you in anyone's timeline.
---

Source: https://geordy.ai/glossary/structured-data/activitypub
This is a machine-readable markdown version of that page, generated by Geordy.