Social networking website Facebook has launched a platform that allows developers to build software on top of the 'social graph' within the site. This launch heralds the end of social networks as closed platforms. Facebook Platform was unveiled with 85 applications from 65 developer partners. Video, a sample application demonstrated during the launch, allows users to share personal videos within the website, and exchange video messages through the Facebook Inbox. Users can upload content shot using their mobile phones directly into the Video applications. Meanwhile, Facebook also unveiled Facebook Markup, a new markup language that allows developers to create applications on the Facebook site. Features include dynamic information tags, conditional privacy tags, image caching and Flash. Developers can create application pages called canvass pages on the Facebook site. These applications will be distributed through a network called social graph, in which users can build and share information. One of the developer partners of Facebook Platform is Microsoft, which is supporting Facebook via Popfly Facebook Bock and Silverlight applications, as well as the Facebook Development Toolkit. Popfly gives access to user information contained in User Profile, Friends, Photos, Photo Albums and Events. Popfly blocks like Flickr, Digg, Soapbox, Twitter, Windows Live, Xbox Live and Virtual Earth can also be used to build Facebook software. The Facebook Development Toolkit can be used to create software for Windows, the Web, or Microsoft Office.