Just like in class, in Moodle we can create different groups according to whichever variable you choose.  You can create groups to work on different projects, to carry out different discussions or you can even use the groups to differentiate your class based on mastery of a learning standard.  The groups feature can easily be used to randomly create groups or you can manually create the groups you want.  Watch the video below for the basics of creating Groups in Moodle.