inetd services

[B0Ti <9915104t@example.com>]

From the inetd manual:

" Inetd provides several ``trivial'' services internally by use of
routines
     within itself.  These services are ``echo'', ``discard'',
``chargen''
     (character generator), ``daytime'' (human readable time), and
``time''  "

What are these services used for? I could guess what "time" and
"daytime" do, but what are the others?
I disabled them all, hope it doesn't hurt anything.

B0Ti.