The two types of system components are as follows:

A library file (or a library) is a component that represents a repository. It stores source code, object code, and persistent objects. For more information on libraries see Library.

A user object is a component that represents a person who can use a library.

Each library has a user object named Library Supervisor. Only a library supervisor can create user objects to give people access to a library. When a library supervisor authorizes you to use a library, the supervisor creates a user object that specifies a unique value (for example, your initials or employee number), your full name, and your network logon ID. For more information on creating user objects, see Giving users access to libraries.