DVI and HDMI are both HDCP complaint digital cable standards.  DVI is slightly older and can only transport a video signal, HDMI is the newer of the two and capable of amazing throughput.  But what happens when you buy a new add-on component with an HDMI output and your TV only has DVI?

Thankfully you can convert between the two standards.  It's best to save the conversion until the very end of the signal path.  This means that if your sending a video signal to a TV's DVI input from a DVD player's HDMI out, use an HDMI cable and use an HDMI to DVI converter to connect it to the TV.  The connections are compatible because of their similarity as high bandwidth digital connections that are able to travel down the wire encrypted only to be decrypted on the other side.

The adapters shown here can really save your HT project from not being able to use the high quality digital connection formats.  You can purchase the cables and adaptors online from places like Ram Electronics a great source for cables and adaptors at very reasonable prices.  If your HT gear is capable of using the new digital formats you should take advantage, but beware of overpaying for these digital cables.  There is nothing to be gained from expensive digital cables made from exotic materials.