RBAC, which stands for role-based access control, is a method of restricting user access on a multi-user computer system. It is frequently utilized by computer security experts at companies with large numbers of employees.
In a RBAC system, access restrictions are defined by role rather than on an exclusively per-user basis. Each user falls into a category of a specific job role, and that role's level of access is defined at the system level. Roles can themselves be part of an RH (role hierarchy), which defines varying levels of inherited permission restrictions.