What is JWT, Cookies and Session

JWT (JSON Web Token) is a compact, URL-safe means of representing claims between two parties. It is commonly used for authentication and authorization purposes in web applications. JWTs are self-contained tokens that consist of three parts: a header, a payload, and a signature. The header typically includes information about the token's algorithm and type, while the payload contains the claims or statements about the user or entity. The signature is used to verify the integrity of the token and ensure that it has not been tampered with. JWTs are often used for stateless authentication, as the server can validate and extract necessary information from the token without the need for server-side sessions.

A cookie is a small piece of data that a website stores on a user's computer or device. It is sent by the server to the client's browser and then returned with subsequent requests to the same server. Cookies are used to store information about the user's interaction with the website, such as preferences, authentication tokens, or shopping cart items. They can be either session cookies, which are temporary and exist only until the user closes the browser, or persistent cookies, which are stored on the user's device for a specific period of time. Cookies enable websites to provide personalized experiences and maintain user sessions across multiple requests.

A session refers to a period of interaction between a user and a server. In the context of web applications, a session typically begins when a user accesses the website and ends when the user closes the browser or remains inactive for a specified period of time. During a session, the server maintains a stateful connection with the user, allowing the user to perform actions and access resources without having to reauthenticate for each request. Session data is stored on the server and can include information specific to the user, such as user ID, preferences, or shopping cart contents. Session management is often achieved using session identifiers, which are stored in cookies or passed through URLs to associate subsequent requests with the appropriate session on the server.