If you want to know your uid or gid:
knilluz@knilluz-desktop:~>id uid=1000(knilluz) gid=100(users) groups=33(video),100(users)(only want the userid: id -u, want to know all groups id’s: id -G, not the id’s but the name of the groups: id -Gn or only the primary group id: id -g or the name of the primary group: id -gn).
To get out of your identitycrisis:
knilluz@knilluz-desktop:~>whoami knilluz
(same result as: id -un but whoami looks just better)
Or just want to know everybody logged in:
knilluz@knilluz-desktop:~> who knilluz :0 2011-05-15 14:36 (console) pietjepuk pts/3 2011-05-15 20:24 knilluz pts/0 2011-05-15 22:30
(or want to know how many users are logged in: who -q [q from count :-)], or show a lot (time last system boot (-b), dead processes (-d), login processes (-l), active processes spawned by init (-p), runlevel (-r), last system clock change (-t), and finaly the users logged in (-u)): who -a)