User ID in Linux
To print user ID in Linux, we can use id command.
id
Example 1 – User Id of root user
In this example, we get the user ID of root user.

We are currently logged in as root.
root@tutorialkart#
To get the user ID of root user, execute the id command.
root@tutorialkart# id uid=0(root) gid=0(root) groups=0(root)
uid
is our user ID. id prints group id gid
and groups
information as well, along with the user ID.
Example 2 – User ID of another user
In this example, we get the user ID of user prasanna (who is logged in right now).

Now we have logged in as another user, say prasanna.
prasanna@tutorialkart#
Let us get the user ID of this user using id command.
prasanna@tutorialkart# id uid=1000(prasanna) gid=1000(prasanna) groups=1000(prasanna) ,4(adm) ,24(cdrom) ,27(sudo) ,30(dip) ,46(plugdev) ,120(lpadmin) ,131(lxd) ,132(sambashare)
Conclusion
In this Linux Tutorial, we learned how to get the user ID of current user using id command.