The Force.com licenses play an important role in the security aspects of the Force.com platform. You can see all these licenses and the statistics about the usage of licenses by navigating to Setup | Administer | Company Profile | Company Information.
There are two types of licenses in the Force.com platform. They are as follows:
User Licenses: Each user must have a user license that defines the access to applications and functionalities. Different types of user licenses allow different levels of access and define which profiles and permission sets are available to the user. There can be more than one type of user license in your organization. There are many types of user licenses. Mainly, we consider the following user licenses: