How Can a Single Password Unlock So Many Accounts?

Imagine you have a key that fits all your doors. You use the same key to open your front door, your bedroom door, and even the door to your neighbor's house. That’s like using one password for many websites, they’re all connected through something called authentication. When you type in your password on a website, it checks if it matches what was stored there, just like checking if the key fits the lock.