Activity Streams is an open format specification for activity stream protocols, which are used to syndicate activities taken in social web applications and services, similar to those in Facebook's, Instagram's, and Twitter's. The standard provides a general way to represent activities.

Prefix
ac
Links
Homepage
Contact
Missing Contact
Pattern for Local Unique Identifiers
Missing LUI pattern
Example Local Unique Identifier
Add   Resolve
Pattern for CURIES
Could not construct CURIE pattern
Example CURIE
ac:Add
Contributor
Charles Tapley Hoyt
Providers

Providers are various services that resolve CURIEs to URLs. The example CURIE ac:Add is used to demonstrate the provides available for ac. Generation of OLS and BioPortal URLs requires additional programmatic logic beyond string formatting.

Name Metaprefix URI
Activity Streams ac http://www.w3.org/ns/activitystreams#Add
Bioregistry bioregistry https://bioregistry.io/ac:Add