Definition
Access control is the process of determining who or what can view, use, or modify resources within a system. It involves granting or denying specific permissions based on established policies and user roles. In practice, this means ensuring that only authorized individuals can access sensitive data or perform critical functions. This is vital for protecting information integrity and preventing unauthorized actions that could lead to breaches or operational disruptions. For instance, a company might implement access control to restrict access to financial records only to accounting personnel. A common point of confusion is differentiating access control from authentication, which merely verifies identity rather than granting permissions. Access control is a core concept covered in certifications like CompTIA Security+ and CISSP.