DTS-HD Master Audio is the latest uncompressed audio format and is available on Blu-ray discs.  With upwards of 7.1 channels of discrete surround sound and connected via copy-protected HDMI cables, DTS-HD Master Audio is at the pinnacle of surround sound technology for home theater.

DTS-HD Master Audio includes the DTS "Core" track which is a lossy format but can be output via digital outputs (like optical or coax). DTS-HD MA has variable bitrates up to 24.5 mbps.

The only two ways to get DTS-HD Master Audio is either via HDMI to a receiver that can decode it, or from a 6-channel analog output from Blu-ray players that have such outputs, and a receiver that has a multi-channel input.

Other DTS resources include:

DTS Surround Sound
DTS Brand Page

Official DTS HD Master Audio Page
Official DTS Website