S/PDIF is a standard for transferring audio in digital format.
You can connect the S/PDIF output from your computer to the S/PDIF input on your home theater receiver. This connection allows you to set up a 5.1 audio
(also known as 6-channel audio) connection.
There are two kinds of S/PDIF connections:
Optical — Set up by optical fiber with TOSLINK connectors
Coaxial — Set up by coaxial cable with RCA connectors