User Authentication and Authorization are security mechanisms that are used to verify the identity of users and control their access to resources within an application.

Authentication refers to the process of verifying the identity of a user, typically by requiring a username and password, or some other form of secure credential. The goal of authentication is to ensure that only authorized users are able to access the application.

Authorization, on the other hand, refers to the process of controlling access to specific resources within the application, based on the authenticated user’s role or permissions. This allows the application to enforce fine-grained security policies and determine what actions a user can perform within the application.

In web development, user authentication and authorization are often implemented using token-based authentication, where the server sends a secure token to the client after a successful login, and the client uses that token for subsequent requests to the server. This allows the server to identify the user for each request, without requiring the user to re-enter their credentials for each request.

Implementing user authentication and authorization is critical for building secure and trustworthy web applications, as it helps to protect sensitive information and ensure that only authorized users are able to access and manipulate data.