You may have a marketing group, different sales groups, a group for the team leads and managers and many such closed groups. Communicating within these closed circles to easily collaborate and share information is a common problem in an organization. You have got a solution to that by creating groups under Feeds. Any discussion going on within a group, files shared within a group, status messages, etc., can be accessed by the users of the group. You can also mention your group in messages or send private messages to the group.
Note
To create a group from the Feeds tab

