Moodle has a very useful tool for manipulating and managing groups of learners and teachers within each course: the Groups functionality. This tool provides an effective way to manage activities, projects, or the complete course. For example, if you, as an instructor, have three periods of the same course, you don't need to set up three different courses; instead, you have just the one course and you organize the different courses into three groups in the course. This functionality is set up at the course level. If, on the other hand, you have one very large course, you can use groups to set up sections.
If you set up groups in the course or at the activity level, you can run the groups completely independent of each other. You can also set them up as partially separate groups, allowing for some interaction, such as each group can see each other groups' activities (for instance, a wiki) but cannot interact or add to the other groups' activities.
To set up groups, they must be enabled in the course settings. Groups are enabled by default. If you don't see the Group icon and link in your course Administration block, contact your Moodle administrator.
There are three group mode options that you will see when you're adding resources and setting up activities: