This is 99% Invisible. I'm Roman Mars.

This sound is unmistakable.

Maybe you find it kind of lulling like I do since it signifies the end of a trip to the grocery store.

You've found all the things on your list and now you get to just stand there and zone out for a second

or flip through a passive magazine while the checkout person does the work.

That's our new producer Katie Mangle. I myself find that sound a bit anxiety inducing since it's also the sound of the total that I'm going to have to pay going up and up and up and up.

When I go to the grocery store and check out, I'm utterly amazed at how well the skaters can read barcodes.

No, I don't tell the checkout people. My wife always did. My husband here is the one that invented that barcode.

And they just kind of look at you as if to say, yeah, I believe that.

Of course today they would look at you as if to say, you mean there was a time they didn't have a barcode?

It's hard to imagine now a world without barcodes, a world without George Laura.

Well, hello, I'm George J. Laura. I'm the one that invented the UPC barcode and symbol in 1973.

Now, some of you might be saying to yourselves, I thought Joseph Woodland invented the barcode.

And if you're saying that to yourself, you are a nerd and I love you for it.

And just hold your nerd horses because we're getting to Woodland right now.

It started the way a lot of things start with people trying to make more money.

The grocery business decided that they needed some way to reduce their overhead.

One of the main places they felt they were losing money was the checkout line.

They came up with the idea of having some kind of a scannable code.

Which would move people more quickly through the line.

One of the first people that started working on it was an engineer named Joseph Woodland.

After working on the Manhattan Project, Woodland moved on to develop an innovative way to produce elevator music.

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