W3C-ACTIVITY-STREAMS

W3C AS2 Activity Streams 2.0 social vocabulary.

Definition

AS2 core types: (1) Activity types: Accept, Add, Announce, Arrive, Block, Create, Delete, Dislike, Flag, Follow, Ignore, Invite, Join, Leave, Like, Listen, Move, Offer, Question, Reject, Read, Remove, TentativeAccept, TentativeReject, Travel, Undo, Update, View. (2) Object types: Article, Audio, Document, Event, Image, Note, Page, Place, Profile, Relationship, Tombstone, Video. (3) Actor types: Application, Group, Organization, Person, Service. (4) Link types: Mention. Properties: actor, object, target, result, origin, instrument, attachment, attributedTo, audience, content, context, name, endTime, generator, icon, image, inReplyTo, location, preview, published, replies, startTime, summary, tag, updated, url, to, bto, cc, bcc, mediaType, duration. Context: '@context': 'https://www.w3.org/ns/activitystreams'. AS2 vs ActivityPub: AS2 = vocabulary data model, ActivityPub = federation protocol (HTTP POST/GET transport + Inbox/Outbox patterns). Adoption Fediverse 12+ million Mastodon users 2024 + ActivityPub adopters Threads Meta (partial), Tumblr (planned).

Origin

Activity Streams 1.0 OpenSocial Foundation 2009 ; AS 2.0 W3C Social Web Working Group 2014 ; AS 2.0 Vocabulary W3C Recommendation 23 May 2017 ; AS 2.0 Core W3C Recommendation 23 May 2017.

Example in context

Mastodon user @claude@mastodon.social posts a Note via ActivityPub: Create activity JSON-LD AS2, actor @claude server, object Note content text 'Hello Fediverse', published timestamp, transmission Inbox @follower@other-instance.org, federation cross-instance.

Related terms

• W3C ActivityPub — federation protocol.