Why is login page important?
The login form gives access to your website or web application and therefore to your data. This form fulfills a fundamental task of security; but many times it is omitted to evaluate if the procedures of user name (user), keys (passwords) and authentication comply with the security recommendations.
How does a login page work?
The user submits the Login Credentials i.e. Username and Password. The server verifies the credentials against the DataBase. The server then generates a temporary Token and embeds the user data into it. The server responds back with the token (in body or header).