Displays information about yourself or another user: UID, GID, effective UID and GID if relevant, and additional GIDs.
Print supplementary GIDs.
With -u, -g, or -G, print user or group name, not number.
Print the output in a more easily read format. Not used with other options.
Print in the format used by the system password file, /etc/passwd.
With -u, -g, or -G, print real, not effective, UID or GID.
Print UID only.