How do QR codes work?

How does the image link to a website, and who developed them? It seems like they are appearing on everything nowadays.

QR codes direct your smartphone (or whatever you use to scan the code) to a website, which then redirects to wherever the manager of that codes wants. There are free QR code generators on the internet, such as

Are you familiar with It takes big long unweildy URLs, shortens them up, and spits out a tiny URL that you can give people to easily navigate wherever you want them to. It’s essentially the same thing, except in a visual format for your phone to use.

LMGTFY QR code - Wikipedia

It’s just a 2-dimensional barcode symbology that can be used to encode a string of alphanumeric data (which can be the URL of a website, or it can just be text or numeric data).