Users on Machine

[Slip]

I am reviewing some accounts on my system, I came across a few accounts that I have no idea which program has created. Anyone know what do these belong to?

daemon:2:2:daemon:/sbin:/bin/false
adm:3:4:adm:/var/adm:/bin/false
lp:4:7:lp:/var/spool/lpd:/bin/false
news:9:13:news:/usr/lib/news:/bin/false
uucp:10:14:uucp:/var/spool/uucppublic:/bin/false
operator:11:0:operator:/root:/bin/bash
at:25:25:at:/var/spool/cron/atjobs:/bin/false
nut:84:84:nut:/var/state/nut:/bin/false
cyrus:85:12::/usr/cyrus:/bin/false

That operator account worries me.

[invertedpanda]

Its a common account. Not really sure what it is for, but it has been on every Linux system I've worked on.

[Fallen Angel]

Yes, it is an account that exists on every Linux system.