# Dan Hollick - QR Codes (Highlights) ![rw-book-cover|256](https://readwise-assets.s3.amazonaws.com/static/images/article2.74d541386bbf.png) ## Metadata **Review**:: [readwise.io](https://readwise.io/bookreview/19523608) **Source**:: #from/readwise **Zettel**:: #zettel/fleeting **Status**:: #x **Authors**:: [[Dan Hollick]] **Full Title**:: QR Codes **Category**:: #articles #readwise/articles **Category Icon**:: 📰 **URL**:: [typefully.com](https://typefully.com/DanHollick/qr-codes-T7tLlNi) **Host**:: [[typefully.com]] **Highlighted**:: [[2022-10-08]] **Created**:: [[2022-10-12]] ## Highlights - When a mask is applied to the code anything that falls under the dark part of the mask is inverted. A white area becomes black and black area becomes white. ([View Highlight](https://instapaper.com/read/1543428787/20907517)) ^394249669 - Perhaps the coolest thing about QR codes is that Denso Wave, the company that invented them, never exercised their patent and released the technology for free! ([View Highlight](https://instapaper.com/read/1543428787/20907524)) ^394249670 Respect