Today, Yahoo opened the developer interfaces to our Y!OS platform stack through the release of the Yahoo! Social Platform (YSP), Yahoo! Query Language (YQL), Yahoo! Application Platform (YAP), and the YDN developer dashboard.  This makes Y!OS a reality for an essential constituency: developers.  Now, anyone on the web has access to Yahoo!’s tools and data to start building applications for Yahoo!’s vast audience and the web beyond.  It’s a great step forward in rewiring Yahoo! with a social dimension and a platform architecture that’s open like never before.

Yahoo! Social Platform (YSP)
See: http://developer.yahoo.com/social

Yahoo! Query Language (YQL)
See: http://developer.yahoo.com/yql

Yahoo! Application Platform (YAP)
See: http://developer.yahoo.com/yap

Caja, security, and user privacy
For more info on Caja: http://developer.yahoo.com/yap/caja

OAuth
See: http://developer.yahoo.com/oauth

OpenSocial Support
This launch also marks Yahoo!’s first implementation of OpenSocial support.
http://opensocialapis.blogspot.com/2008/10/launched-yahoos-first-implementation-of.html

Hats off to Yahoo!
Y!OS is out there.  Yahoo! is Open.