File permissions “newbie help file”

Sensei writes “One of the things that makes Unix different from Windows are file ownership and permissions. All files are on a Unix system are owned by a user and a group. Users own files they create, and root can change the ownership of files through the “chown” utility. A file’s group is set to the primary group of the user that creates it initially. Since users can belong to more than one group (and often do), a user can change the group of any file they own with the “chgrp” utility to any group they belong to. You can use the “groups” utility to list what groups you (and others) belong to.” Read more at Linuxnewbie.org.