Page 2-5: Figure 2-1, entitled Common Uses for Roles, shows four vertical layers. The topmost layer, labeled Users, is an illustration of five terminal users or clerks. The next layer down is labeled User Roles, and shows that the two leftmost terminal users have the PAY_CLERK Role. The center user has the MANAGER Role, and the two rightmost users have the Receiving Clerk (REC_CLERK) Role. The third layer is labeled Application Roles and shows that both the PAY_CLERK and MANAGER user roles are included in the Accounts Payable (ACCTS_PAY) application role. The Manager is also included in the Accounts Receivable application role, as are the two clerks whose User Role is REC_CLERK. The bottom layer is labeled Application Privileges, and shows two separate applications: the Accounts Payable application (ACCTS_PAY) and the Accounts Receivable application (ACCTS_REC). The privileges to execute the Accounts Payable application apply to the associated application and user roles, ACCTS_PAY and PAY_CLERK and MANAGER. The privileges to execute the Accounts Receivable application apply to its associated application and user roles, ACCTS_REC and REC_CLERK and MANAGER.