The video goes through how QR codes work.
Quote from the video:
“QR codes became so popular they are now ubiquitous”
Truly.
YouTube – Veritasium – I used to hate QR codes. But they’re actually genius
As it’s Veritasium it’s slightly nerdy, and to use QR codes you don’t need to know any of this. Even less if you use CliqTags, as a QR code is auto-generated for each site.