Basic user operations on a Linux box

users.sh

# add user to linux and create home directory (remember to change SHELL in /etc/passwd)
useradd -m USER

# set password
passwd USER

# add to extra groups, no change on primary
usermod -a -G GROUP1,GROUP2 USER

# list groups a user belongs to
groups USER1 USER2

# delete user and home directory
userdel -r USER

# create a group

groupadd GROUP