New HDMI features are in development all the time, but here are some standard features of HDMi cables up to version 1.3b.

• Consumer Electronic Control (CEC)
  CEC allows HDMI devices to control each other through the HDMI cable itself. This allows the user to operate several devices with one remote control (requires compatible hardware). 
  
  
• Enormous bandwidth capacity
  Up to 10.2 gigabits per second, more than twice the bandwidth needed to transmit a 1080p signal, such as the output from a Blu-ray Disc player. This also allows for future resolutions, like 1440p, or Quad HD.
  
  
• 8 channel audio
  HDMI supports up to 8 channels of audio, Dolby Digital, DTS, and Super Audio CD. With version 1.3, HDMI supports lossless compressed audio streams Dolby TrueHD and DTS-HD Master Audio.
  
  
• Deep Colour
  Takes the HDTV palette from millions to trillions of colors.
  
  
• Blue Ray Support
  Supports Blue Ray at full audio and visual resolution.
  
  
• Auto Lip-sync
  Ensures your audio and video streams stay in time with one another.
  
  
• HDCP
  HDCP is designed to help protect copyrights on digital media. HDMI can use HDCP to encrypt the signal. Some regions and organisations require the use of HDCP on HDMI when playing back encrypted DVD Video, DVD Audio, and Blu-ray Disc.
  
  
• Compatibility with DVI
  A DVI signal is basically compatible with an HDMI signal. When an HDMI - DVI adapter is used there is no conversion in the data, and so you see no loss in video quality at all. As such, HDMI is backward-compatible with DVI digital video (DVI-D or DVI-I, but not DVI-A) This means that a DVI-D source can drive an HDMI monitor, or vice versa, by means of a suitable adapter or cable. However, not all features of the HDMI cable may be used, such as CEC or HDCP.