What isd the Purpose of the Rs 232 jack?

I walked into radioshack yesterday to look for some cables and i noticed thay had the cable exactly named "Rs-232c" like on back of the mpc 60 i was asking what is the cable used for like always radioshacks didnt have the answers to the questions,anyway if anybody knows what this port is used for let me know
thanks

id be interested to know as well for my s950, would be nice to hook up a zip drive

From what I remember, off the top, I believe it was put there as a way to interface with computers for various reasons.

Apparently it wasn't fully implemented though.