From the brains behind brains on, this is Moment of Um.

Moment of Um comes to you from APM Studios. I'm Kip Wellington, the codebreaker extraordinaire.

I love hidden messages, sneaky symbols, covert codes, you know, secrets.

If you have a message that you need to unscramble, I'm your guy.

I know tons of different kinds of codes, like Morse code with all the dots and dashes.

Or semaphore, where you spell out the words with flags.

But you know which code I can't crack?

QR codes.

You know those little black and white squares that look like they're made out of random, scattered

dots?

You can find them in all kinds of places, restaurant menus, concert tickets, even food labels.

You just point your phone camera at the code and, ta-da!

Your phone goes to a specific website. But how does the phone camera at the code and, ta-da, your phone goes to a specific

website. But how does the phone know where to go? Where's all the information? M and I both needed to know.

QR codes. What is your secret?

In order to understand how QR codes work, we have to first understand what they're designed to replace.

And that's barcodes.

My name is Sam Dickerson.

I'm an associate professor of electrical and computer engineering at the University of Pittsburgh.

So think of the barcodes that you see at the supermarket on any product

that you see on the store. And what a barcode does is it represents information visually.

There are parallel lines that are specified with in space such that they can represent different numbers and letters. And then at the

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