Vehicles as they were assembled
Packages behind the scenes at UPS
To initiate phone calls
As an alternative to website URLs
 
Correct Answer: Vehicles as they were assembled

A little background…

The QR (Quick Response) code was created in 1994 by former Toyota subsidiary Denso Wave as a means of quickly tracking vehicles and parts through their manufacturing process. Although Denso holds the patent to QR codes, it has made the technology free for anyone to use.

An early version of the two dimensional bar code system measured only 21 x 21 modules and contained just four characters of data, while the largest current version (40) spans 177 x 177 modules and can hold 1,264 characters of ASCII text or up to up to 7,089 numerals.

Fast fact: In 2014, Heinz shipped ketchup bottles with an outdated QR code that brought customers to a porn site.