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 Specs and RFCs used
 ===================
 
-* [OStatus](https://www.w3.org/community/ostatus/wiki/images/9/93/OStatus_1.0_Draft_2.pdf)
-* [Salmon](http://www.salmon-protocol.org/salmon-protocol-summary)
-* [Portable Contacts](https://web.archive.org/web/20160305010620/http://portablecontacts.net/draft-spec.html)
-* [Atom](https://tools.ietf.org/html/rfc4287)
-* [Atom ActivityStreams](http://activitystrea.ms/specs/atom/1.0/)
-* [Atom Threading](https://tools.ietf.org/html/rfc4685)
-* [PubSubHubbub](https://pubsubhubbub.github.io/PubSubHubbub/pubsubhubbub-core-0.4.html)
-* [Webfinger](https://tools.ietf.org/html/rfc7033)
-* [Link-based Resource Descriptor Discovery](https://tools.ietf.org/html/rfc6415)
+* [OStatus](https://www.w3.org/community/ostatus/wiki/images/9/93/OStatus_1.0_Draft_2.pdf)  
+  Suite of federation protocols
+  * [Salmon](http://www.salmon-protocol.org/salmon-protocol-summary)  
+    Delivery of targeted events to users
+  * [Portable Contacts](https://web.archive.org/web/20160305010620/http://portablecontacts.net/draft-spec.html)  
+    Encoding profile information in Atom
+  * [Atom](https://tools.ietf.org/html/rfc4287)  
+    Representing user feeds
+  * [Atom ActivityStreams](http://activitystrea.ms/specs/atom/1.0/)  
+    Encoding rich social post metadata
+  * [Atom Threading](https://tools.ietf.org/html/rfc4685)  
+    Encoding chains of conversations
+  * [WebSub](https://pubsubhubbub.github.io/PubSubHubbub/pubsubhubbub-core-0.4.html) (formerly PubSubHubbub)  
+    Broadcasting of real-time updates to followers
+* [WebFinger](https://tools.ietf.org/html/rfc7033)  
+  User-on-domain lookups
+* [HTTP Signatures](https://tools.ietf.org/html/draft-cavage-http-signatures-06)  
+  Server-to-server authentication of requests
+* [ActivityPub](https://www.w3.org/TR/activitypub/)  
+  Federation protocol