Facebook Groups are slightly different from Facebook Pages. Groups can be based on common interests, activities, or anything you like. The Facebook Groups application page will displays your groups and your friends groups. With Facebook, you can join and create up to 200 groups.
Group makes it possible to send mass invitations. You can easily invite all your friends to join the group. This means that each group member can also send mass invitations to their friends.
Group have administrators who manages the group, approved the applicants or invite others to join. Administrators can also designate a person who has the ability to manage the group to become an officer.
Groups offer much greater control over who can participate. Permissions settings allows the group admin to restrict access to a group, so that new members must be approved.