Social Web Bookmarks

[PDF] OStatus lets people on different social networks follow each other. It applies a group of related
protocols (PubSubHubbub, ActivityStreams, Salmon, Portable Contacts, and Webfinger) to this problem in what we believe is a simple and obvious way

Zot is a WebMTA which provides a decentralised identity and communications protocol using HTTPS/JSON.

The ActivityPub protocol is a decentralized social networking protocol based upon the [ActivityStreams] 2.0 data format. It provides a client to server API for creating, updating and deleting content, as well as a federated server to server API for delivering notifications and content.