Login using Javascript without a backend server

Question

How to get and send data without backend server?

I took on a project to create a login using JavaScript. Does it make sense to create my own JSON file? Where is the data stored using localstorage?

Answer 1

I'm pretty sure that if you store the password on the client side without requiring authentication from the backend, the client can just search to find the password stored on its side. If you don't care about that, as far as I know you can store their data in cookies or in local storage.