User roles enable the Administrator to define standard user privileges for the system to ensure that users only have access to the menu screens and functionality that are required for their role. For example, only selected employees may have the ability to generate job cards, create purchase orders or generate sales invoices.
Access privileges are not set for individual users, but for each user role within the company. It is easier to control who has access to what and means that if you have a number of employees performing the same or similar jobs, any changes you wish to make to their system access levels can be done once, rather than individually.