Session is a state management technique that is used to manage the state of a page with the help of session data. In simple words, to save the time for unwanted requests by the users we use Session to store the necessary data. Session state uses a store maintained by the app to persist data across requests from a client. The session data is backed by a cache and considered ephemeral data. The site should continue to function without the session data. Critical application data should be stored in the user database and cached in session only as a performance optimization. Session data are the secured technique to transfer the data from page to another page and these data can only being used by the particular browser, no one can use that session even in the same computer other browsers can't able to use it.