How do QR codes work?

QR codes allow symbols, phrases and URLs to be hidden from sight. But how do they work?

A QR Code (QR stands for ‘quick response’) is a two-dimensional matrix barcode that consists of a series of black modules arranged in a square pattern on a white background. They work by embedding a series of information within preset boundaries, the data being located and identiﬁed by a series of alignment, timing and positional patterns within the code.

The codes are read by scanners and smartphone cameras installed with a QR-deciphering software (these tend to be freely available as apps, or in some cases, are natively installed in the phone’s ﬁrmware). In practice, this allows any smartphone user to hold their device up to a QR code and decipher its encrypted data, receiving a message, image or URL link.

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