After you have added people to your chat Contact List, you can organize them into groups.
Click anyone in your chat Contact List and use a drag-and-drop operation to move them to the group you want to add them to.
What else do I need to know?
You can chat only with people in your Contact List.
You have to add a person to your Contact List before you can add them to a chat group.
What if I want to know more?