What principle underlies the process of granting user access to system resources?

The fundamental principle underlying user access to system resources is authentication and authorization. First, the system verifies the user's identity (authentication), for example, through a login and password. After confirming the identity, the system determines which resources and actions are permitted for this user (authorization), based on their roles or rights.

Example: the user enters a login and password, the system verifies them, then checks which data or functions they have access to, and either allows or denies the operations.