1. Version 1.0 - HDMI v1.0 was the original format, released in December 2002. It took DVI's video signal format and added in the ability to carry a Dolby Digital or DTS bitstream or only two channels of PCM audio (48kHz, 24-bit). The two-channel PCM restriction worked fine for connections between cable/satellite receivers or DVD players and a stand-alone HDTV (which only supported two channels of audio) but it wouldn't be able to support the new audio formats that were slated to accompany HD optical discs (HD-DVD and Blu-ray). Adoption of HDMI v1.0 was sluggish, as DVI-HDCP had a headstart in the market. It didn't help that HDMI shares DVI's cable length restriction – anything more than about 15 meters violates the specification and is likely to require either a booster or a conversion to fiber optic.

2. Version 1.1 - It was with Version 1.1 (released in May 2004) that HDMI was finally able to make a compelling argument for superceding DVI-HDCP. HDMI could now carry multichannel PCM audio (eight channels at 192kHz, 24-bit) in addition to Dolby Digital and DTS compressed bitstreams. Version 1.1 also added support for passing the bitstream data from DVD-Audio discs, which previously had to be decoded inside the player and output as six channels of analog or passed as a bitstream through IEEE-1394 (also called FireWire or iLink, a connection type that never saw widespread adoption).

3. Version 1.2 - HDMI v1.2 was adopted in August 2005 (v1.2a was adopted in December 2005 and added some testing and certification language). The only notable difference between it and v1.1 is support for a DSD (one bit audio) digital bitstream. This means that a player can now send the raw digital signal from an SACD over HDMI to a receiver or processor, eliminating the need for decoding of the DSD signal at the player.

4. Version 1.3 - The HDMI v1.3 spec has been official since Q3 2006, however it took nearly six months for the first HDMI v1.3 sources to appear (the Playstation3), and close to a full year to see the first HDMI v1.3 receivers, and we're just now starting to see announcements for HDMI v1.3 displays. The main change to HDMI with v1.3 is the video bandwidth, which increases from 165MHz to 340MHz (10.2Gbps). This change allows HDMI to carry video signals with 30-bit, 36-bit, or 48-bit color depths (previous versions were limited to 24-bit color depth).