P4G8X audio module question

Does anyone know what this module is for, for the P4G8X Dlx mobo:

Digital Audio COnnector (6-1 pin SPDIF)
"This connector is for the S/PDIF audio module to allow digital sound input/output. Connect one end of the s/pdif audio cable this connector and the other end to the s/pidif module"

Not sure what its used for, can someone give me some examples on what it is used for.

Thanks

You can run a digital cable from your computer to your home theater system for digital audio quality.