Basics
HDMI stands for High Definition Media Interface and was introduced in 2002. It is used with high-definition media players, such as Blu-Ray players or game consoles as on the Xbox 360. The cable is capable of transferring high-definition video at a maximum resolution of 1920-by-1080 pixels (1080p) as well as digital audio.
Availability
All Xbox 360s manufactured after 2007 have HDMI ports on the back for connecting them to TVs using an HDMI cable. The only model that does not support HDMI output is the original Core console, released in 2005, which is a bare bones console for casual gamers. Before 2007, the only Xbox 360 consoles with HDMI output were the Pro model consoles, which also came with a 60 GB or 20 GB hard drive, something the Core consoles lacked.
Cable Types
The type of HDMI cable used does not typically matter since the signal is digitized before it is transferred. Microsoft sells an official Xbox 360 HDMI cable on its website, however any HDMI cable will work just fine. No consoles come officially packaged with an HDMI cable and instead include the alternative component or composite cables.
Alternatives
Component and composite cables are the alternative to using an HDMI cable with an Xbox 360. Composite cables are only for standard definition TVs and are not capable of transferring resolutions higher than 720-by-480 pixels. Component cables are slightly better, but can only produce an image of 1440-by-1080 pixels (1080i). Component and composite cables also use three different chords, while the HDMI uses only a single chord, making it neater than the alternatives.