---
id: activity-pub
title: activity pub
type: concept
tags: []
created: 2026-06-22
---

# activity pub

## Core idea
ActivityPub is a protocol and open standard for decentralized social networking and Fediverse, such as mastodon, pixelfed, lemmy, etc. 
It provides a client-to-server (C2S) API for creating and modifying content and a federated server-to-server (S2S) protocol for delivering notifications and content to other servers. 
ActivityPub uses the ActivityStreams 2.0 format for building its content, which itself uses JSON-LD. The three main data types used in ActivityPub are Objects, Activities and Actors. 
[[OET]] prefers the use of decentralized social networking technologies vs. centralized or monopololized and ad-driven technology.

## Links
https://activitypub.rocks

[[W3C Consortium]]
[[Fediverse]]


[OET]: OET "OET"

[W3C Consortium]: <W3C Consortium> "W3C Consortium"
[Fediverse]: Fediverse "Fediverse"