$ curl cheat.sh/
# useradd
# Create a new user.
# See also: `users`, `userdel`, `usermod`.
# More information: <https://manned.org/useradd>.

# Create a new user:
sudo useradd username

# Create a new user with the specified user id:
sudo useradd --uid id username

# Create a new user with the specified shell:
sudo useradd --shell path/to/shell username

# Create a new user belonging to additional groups (mind the lack of whitespace):
sudo useradd --groups group1,group2,... username

# Create a new user with the default home directory:
sudo useradd --create-home username

# Create a new user with the home directory filled by template directory files:
sudo useradd --skel path/to/template_directory --create-home username

# Create a new system user without the home directory:
sudo useradd --system username

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