tldr/pages/common/usermod.md

usermod

Modifies a user account

• Change a user's name

usermod -l {{newname}} {{user}}

• Add user to supplementary groups (mind the whitespace)

usermod -a -G {{group1,group2}} {{user}}

• Create a new home directory for a user and move their files to it

usermod -m -d {{/path/to/home}} {{user}}