id

Display current user and group identity. More information: https://www.gnu.org/software/coreutils/manual/html_node/id-invocation.html.

• Display current user's ID (UID), group ID (GID) and groups to which they belong:

id

• Display the current user identity:

id -un

• Display the current user identity as a number:

id -u

• Display the current primary group identity:

id -gn

• Display the current primary group identity as a number:

id -g

• Display an arbitrary user's ID (UID), group ID (GID) and groups to which they belong:

id username