HDMI is a digital video/audio signal format which, since its introduction just a few years ago, has taken the home theater world by storm. An HDMI cable consists primarily of a set of shielded twisted pairs which carry video data, together with embedded audio, at extremely high bitrates. While analog component video cable is, in practice, every bit as good a method of delivering video to displays as HDMI cable, the content-providing industries have strongly supported HDMI because it provides a platform for the implementation of HDCP (High Definition Content Protection) to prevent consumers from having complete access to the contents of high-definition digital recordings.
As one might expect from a standard that was developed more to serve the content providers than to aid the consumer, HDMI has presented a few problems. Unlike analog component video, the signal is not robust over distance because it was designed to run balanced when it should have been run unbalanced (SDI, the commercial digital video standard, can be run hundreds of feet over a single coax without any performance issues); the HDMI cable is a complicated rat's-nest arrangement involving nineteen conductors; switches, repeaters and distribution amplifiers for use with HDMI cable, by virtue of this complicated scheme, are made unnecessarily complicated and troublesome; and the HDMI cable plug is prone to falling out of the jack with the slightest tug.