Depending on what you are going to use the system for, you'll need different parts of the above listed things. If you are selling services such as massage or haircut services you'll need to define your Services and your Workers that will be conducting these services. If you on the other hand sell group events such as Yoga classes you'll need to define your Classes, your Resources such as a room where the class will be held and your Workers whom will both be used conduct these classes. And if you for instance sell time slots to tennis courts, you'll need to define your Resources (such as tennis court) and your rules for how these time may be booked. It's all quite easy and straight forward once you know what you want to do, but if you hesitate at any time, we'll be happy to help you on your way.