Linux: Users and Groups Management

Change user/group file ownership (use -R switch to apply changes recursively):
chown user:group <file or directory>

Put a user in the administrator’s group (which enables login + sudo privileged access):
adduser <user> adm

Change file permissions (use -R switch to apply changes recursively):
chmod <permission> <file or directory>
	Permissions:
	0 – None
	1 – Execute
	2 – Write
	4 – Execute
	Permissions are given for user:group:other_users:
	Example:
	 644 – Means: user 2+4 (rw), group: 4(r), other users: 4 (r)