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That a great question! Here’s a small breakdown in terms of difference between login and signup:
This is typically the process a user undergoes when they first interact with your application. When a user signs up, they’re creating a new account. This could be done by providing an email and a password, or by using a social provider like Google, Facebook, etc.
Logging in is the process a user undergoes when they want to access their existing account. They can log in using the credentials they created during the sign-up process (i.e., their email and password), or by using the same social provider they used to sign up.
When using social providers like Google, the process can indeed look very similar. In both cases, users are redirected to the social provider’s page where they authenticate, and then they’re redirected back to your application.
The main difference is that when a user clicks “Sign Up” and authenticates with a social provider, Auth0 will attempt to create a new user account. If an account associated with that social provider’s email already exists, Auth0 will not create a new account, and will instead just log the user in.
When a user clicks “Log In” and authenticates with a social provider, Auth0 will not attempt to create a new account, and will instead just try to log the user in. If no account associated with that social provider’s email exists, the login will fail.
In other words, the sign-up process can also log users in, but the login process can’t create new user accounts. It’s also worth mentioning that, from a security standpoint, it’s usually best to keep these processes separate to avoid confusion and potential security risks.
I hope it will help you!
Thanks and have a great day!