What is S/PDIF I/O used for?

[dabluesman]

While looking at audio cards I noticed that many have this S/PDIF. It is usualy in the form of an RCA jack. Is it like another input for say like a drum machine might have RCA connectors instead of 1/4 jacks, so the S/PDIF is where the drummachine's RCA's would connect? Or is it totaly different, like used only to run out to a DAT digitaly or something. I'm just wondering if I'll need one or not. Thanks!

[pglewis]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by dabluesman:
Or is it totaly different, like used only to run out to a DAT digitaly or something. <HR></BLOCKQUOTE>

*DING DING DING*

Advance to the bonus round! Yes, it's a digital connection and will not work with analog signals.