Kinect for Xbox 360, or simply Kinect (originally known by the code name Project Natal), is a motion sensing input device by Microsoft for the Xbox 360 video game console. Based around a webcam-style add-on peripheral for the Xbox 360 console, it enables users to control and interact with the Xbox 360 without the need to touch a game controller, through a natural user interface using gestures and spoken commands. The project is aimed at broadening the Xbox 360's audience beyond its typical gamer base. Kinect competes with the Wii Remote Plus and PlayStation Move with PlayStation Eye motion controllers for the Wii and PlayStation 3 home consoles, respectively.

Kinect was launched in North America on November 4, 2010, in Europe on November 10, 2010, in Australia, New Zealand and Singapore on November 18, 2010, and in Japan on November 20, 2010. Purchase options for the sensor peripheral include a bundle with the game Kinect Adventures and console bundles with either a 4 GB or 250 GB Xbox 360 console and Kinect Adventures.
After selling a total of 8 million units in its first 60 days, the Kinect holds the Guinness World Record of being the "fastest selling consumer electronics device". 10 million units of the Kinect sensor have been shipped as of March 9, 2011.

Microsoft has released of a non-commercial Kinect software development kit for Windows on June 16, 2011, with a commercial version following at a later date. This SDK will allow .Net developers to write Kinecting apps in C++/CLI, C#), or Visual Basic .NET.

Source: Wikipedia, "Kinect", available under the CC-BY-SA License.