High-definition multimedia interface cables are the primary cables used to transmit high-definition digital video and audio data to consumer visual media displays.
HDMI technology was first released to the market in December 2002. This was around the same time that high-definition televisions first hit the mainstream market. HDMI cables were developed to reduce the amount of cords necessary to transmit both digital video and digital audio to HD-capable devices.
HDMI cables take encrypted, uncompressed digital video and audio from an HD-capable source such as a Blu-ray Disc player, HD-capable digital cable box or computer and allow them to be displayed on HDTVs and high-definition monitors.
HDMI technology enables a user to get both video and audio to an HDTV or computer monitor using only one cable. This is an improvement over DVI cables, which only transmit video.
As the length of HDMI cable increases, there is an increased risk of signal degradation. For instance, most HDMI cables are unable to transmit true 1080p resolution signal beyond distances of 50 feet. HDMI version 1.3, which provides support for Deep Color, has a signal degradation range of less than 20 feet.
PCs can be attached to HDTVs if the PC has an HDMI-out port or contains a graphics card with a DVI port and a DVI to HDMI cable is used.