Understanding Authentication and Authorization in Web Applications:

1. Session: In web development, a session refers to the period of time a user interacts with a website or web application. Sessions are used to maintain stateful information between HTTP requests. Typically, a unique session identifier is stored either in a cookie or in the URL to associate subsequent requests with the same session data on the server.

   1. Example: Shopping Cart in an E-commerce Website

   2. Use Case: When a user adds items to their shopping cart on an e-commerce website, the website stores this information in a session. This allows the website to maintain the user's shopping cart state as they navigate through different pages or perform actions like adding or removing items.

2. Cookie: A cookie is a small piece of data stored on the user's computer by the web browser. Cookies are often used to store user preferences, session identifiers, and other information. They are sent with each HTTP request to the server, allowing the server to identify the user and maintain session state.

   1. Example: Remember Me Option on a Login Page

   2. Use Case: When a user selects the "Remember Me" option on a login page, a cookie is stored on their device containing a unique identifier. The next time the user visits the website, they are automatically logged in using the stored cookie without having to enter their credentials again.

3. JWT (JSON Web Token): JWT is a compact, URL-safe means of representing claims to be transferred between two parties. It is commonly used for authentication and authorization in web applications. JWTs consist of three parts: a header, a payload, and a signature. They are digitally signed to ensure data integrity and can be decoded by the recipient to extract the claims.

   1. Example: Authentication in a Mobile App

   2. Use Case: A mobile app authenticates users using JWTs. After a user logs in, the server issues a JWT containing the user's identity and other relevant information. The app stores this token locally and includes it in subsequent API requests to access protected resources

4. Token: In a broad sense, a token is a credential representing the right to access a resource. Tokens are commonly used in authentication and authorization mechanisms. They can be issued by an identity provider (such as a server or service) and presented by a client (such as a user or application) to access protected resources.

   1. Example: Access Token for OAuth 2.0 Authorization

   2. Use Case: A user grants a third-party application access to their Google Drive account using OAuth 2.0. After the user authorizes the application, Google issues an access token to the application. This token allows the application to make requests to the user's Google Drive API on their behalf without needing the user's password.

5. SSO (Single Sign-On): SSO is an authentication process that allows a user to access multiple applications or services with a single set of login credentials. Instead of requiring separate logins for each application, SSO enables users to authenticate once and gain access to all authorized resources without being prompted to log in again for each application.

   1. Example: Logging into Multiple Company Systems with One Account

   2. Use Case: An employee at a company uses a single set of credentials (username and password) to access various internal systems such as email, HR software, and project management tools. With SSO, the employee logs in once and gains access to all authorized systems without needing to enter credentials separately for each.

6. OAuth 2.0: OAuth 2.0 is an authorization framework that allows third-party services to access a user's resources without exposing the user's credentials. It enables users to grant limited access to their resources (such as data or APIs) to another application, without sharing their username and password. OAuth 2.0 uses tokens to authenticate and authorize access between different parties.

   1. Example: Signing into a Website with Facebook or Google

   2. Use Case: When signing up for a new service or website, users are often given the option to sign in using their existing social media accounts such as Facebook or Google. OAuth 2.0 is used in this scenario to allow the service to request access to the user's social media profile information without needing their password. The user is redirected to the social media provider's login page, where they authenticate and authorize the service to access their profile. Upon authorization, the service receives an access token to access the user's information.

In summary, these terms are all related to authentication, authorization, and maintaining user sessions in web applications, but they have different roles and mechanisms for achieving these goals.