Written by Ron Lyons, Jr. If you're vigilant, you can find QR codes everywhere. These black-and-white squares tie the real world to the internet, and scanning them gives you quick access to ID ...

and eyes of your QR code. You can also add a custom logo to the center of your QR code, although that’ll require the pro membership. The app also offers a neat little randomize button ...

QR Codes are a two-dimensional type of matrix barcode that are used for a variety of uses. They’re one way of turning a long piece of string data into an easily machine-readable format.

The QR code (short for Quick Response code) was invented in 1994 by Denso Wave, a former subsidiary of Toyota, as a means of efficiently tracking vehicles and parts during the manufacturing process.