When a user provides a username and password to log in to a system, it is commonly referred to as Authentication.

Authentication is the process of verifying the identity of a user or system, ensuring that the entity trying to gain access is who it claims to be.

During the authentication process, the user enters their username (a unique identifier assigned to them) and a password (a secret code known only to them) to prove their identity.

Upon successful authentication, the user gains access to the system and its resources based on their permissions.

It is crucial to use strong and unique passwords to enhance security and prevent unauthorized access to sensitive information.