SHELL

linux show groups

cut -d: -f1 /etc/group | sort

linux list groups

cat /etc/group

cat /etc/groups | grep <groupname>
  
# Example:
cat /etc/groups | grep sudo
# Output
sudo:x:27:<user1>, <user2>, <user3>...

# sudo : group name
# x : password (encrypted for security reasons)
# 27 : could be another number, represents group ID
# list of users in group

list user groups linux

groups

linux show groups

cut -d: -f1 /etc/group | sort

linux list user group

groups [user name]
# [user name] : (optionnal) the user to list the group of
#                           default is the one executing the command.

linux user groups

 groups $username

list groups linux for user

groups userName-Here