Flock is a web browser that specialises in providing social networking and Web 2.0 facilities built into its user interface. Until the current version, Flock used the Gecko HTML rendering engine by Mozilla.  The upcoming version 3 will use the Chromium rendering engine.
Flock integrates social networking and media services including MySpace, Facebook, YouTube, Twitter, Flickr, Blogger, Gmail, Yahoo! Mail, etc. Notably, when logging into any of the supported social services, Flock can track updates from friends: profiles, uploaded photos, and more. Flock has Twitter Search functionality, multi-casting of status updates to multiple services, and the introduction of instant messaging via Facebook Chat in the browser.
Other features include:
* native sharing of text, links, photos and videos
* a “Media Bar” showing preview of online videos and photos as well as subscription to photo and video feeds
* a feed reader supporting Atom, RSS, and Media RSS feeds
* a blog editor and reader, allowing direct posting into any designated blog
* a Webkit-mail component allowing users to check supported web-based email off site, compose new messages, and drag-and-drop pictures and videos from the “Media Bar” or webclipboard into a new email message
* support for third-party add-ons, including a number of Firefox extensions.
For Mac OSX, versions are also available for Windows and Linux.