How does the Back button in a web browser work?

Question

I searched the Web about this question but I found nothing:

What is the logic of the back button? What is happening when we hit the back button on a Web browser?

Answer 1

I like to think of it as re-issuing my last request. If you performed a simple GET, it would probably return the same thing it did last time (minus dynamic content). If you had done a POST, you're going to resubmit the form (after confirmation) to the server.