Definition
Access refers to the ability of a user, device, or process to interact with a system or resource. This interaction can range from simply viewing data to modifying or deleting it, depending on the permissions granted. In practice, access control mechanisms like authentication and authorization determine who or what can access specific resources and what actions they can perform. Proper access management is crucial for maintaining data confidentiality, integrity, and availability, preventing unauthorized disclosure or modification. For instance, a user might have read-only access to a financial report but not the ability to alter its contents. It is important to distinguish access from authentication, which merely verifies identity, while access defines what that verified identity is allowed to do. Concepts of access are fundamental to security domains tested on exams like CompTIA Security+, CySA+, and CISSP.