How does a website remember you?
A cookie is a small amount of data stored on a user’s computer and sent back with various requests. In short, it’s typically a user ID. Once a website understands who you are, it can deliver information relevant to you specifically—shopping carts, user dashboards, targeted ads, and much more.
What happens if you clear your cookies? You will be logged out of websites since they will no longer recognize who you are until a new cookie is set, shopping carts reset, and so on.
That’s how websites remember you in a nutshell.