It is a simple login and registration system is totally based on core PHP. This script fulfills all the basic to advance level login needs that a coder or a developer usually require. It is completely secure and uses MySQL.
As an overview of this module, it is focused on simple user sign up with proper field validations, sessions management i.e. how after getting sign in it maintains the logged-in status throughout the user visit with remember me specialty.
The best part of the script is that after registration a user will receive an email to activate the account and after his confirmation only he will get registered. Apart from it you can also allow user to reset or update a password to a new one.
If you got stuck and need to implement such similar system than it is the safe, easy plug and play thing to get you started. You can also modify as per your needs.