TALK, NTALK why is it enabled

[sexy_guy]

I did a

grep disable /etc/xinetd.d/* |grep no

on my server today and found the following services open.

/etc/xinetd.d/cpimap: disable = no
/etc/xinetd.d/ntalk: disable = no
/etc/xinetd.d/pop-3: disable = no
/etc/xinetd.d/talk: disable = no

Is there a reason why ntalk and talk are open? What is this used for?

And the on my other severs i only found the following open

/etc/xinetd.d/cpimap: disable = no

Howabout pop? And yet it works