'Group Dynamics' is a very complex topic. There are various definitions for groups, namely scientific ones and non-scientific ones. This assignment specializes in the scientific definitions. A lot of scientists concern themselves with the formation, the types, and the complexity of groups. However, the views of the scientists differ according to this topic. This assignment investigates the nature of groups as well as the specific form of informal groups. Informal groups have nearly the same nature as formal groups. The differences are demonstrated in the second part of the book.