In the attendee types area you specify what types of tickets you will be selling, whether you need to use the Fast Book option and if this attendee type is to be uploaded to your web page.
For each ticket, or attendee type, you can set a ticket price and a maximum allowed.
You can also set a default attendee type.
For example at your event you might have a guest attendee type with a ticket price of $150 and a member attendee type with a ticket price of $50.