userdel

Userdel is a command used on Unix-like operating systems to delete a user account from the local system. It removes the user’s entries from the system account databases (such as /etc/passwd and /etc/shadow) and from group structures (such as /etc/group) so the account can no longer be used to log in. By itself, userdel does not delete files owned by the user on the filesystem; those files usually remain unless explicitly removed.

Usage and options can vary by distribution, but common behavior is consistent across many Linux systems. The basic form is: userdel [options] username. The most frequently used option is -r, --remove-home, which requests that the user’s home directory and mail spool be deleted as part of the removal process. Another common option is -f, --force, which attempts to remove the user even if the account is currently in use or the system has limitations preventing removal.

Typical considerations:

- The user should not be logged in, and no processes should be running under that user, to avoid issues. Administrators may terminate related processes and sessions before removal.

- After deletion, files owned by the user remain unless removed separately; use find or similar tools to locate and address them if needed.

- On some systems, auxiliary tools (such as deluser on Debian-based systems) offer similar functionality with different syntax or additional prompts.

See also: useradd, deluser/delgroup, passwd. The exact behavior and options can vary between Linux distributions and other Unix-like systems.