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 http://www.qrstuff.com/.

Are you familiar with Tinyurl.com? 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).