What is a QR code and how does it work?
QR stands for 'Quick Response.' A QR code is a square grid of black and white squares that stores information a camera can read instantly — most often a website link, but also text, contact details, Wi-Fi logins, and more.
How a QR code stores data
The pattern of squares (called modules) encodes data in two dimensions — across and down — which is why a QR code holds far more than a traditional one-dimensional barcode. The three large squares in the corners are 'finder patterns' that tell a scanner where the code is and how it's rotated, so you can scan it from almost any angle.
What QR codes are used for
- Opening a website, menu, or app download page.
- Joining a Wi-Fi network without typing the password.
- Sharing contact details as a digital business card.
- Tickets and boarding passes, payments, and product packaging.
Built-in error correction
QR codes include redundant data so they still scan even if part of the code is dirty, faded, or covered — up to roughly 30% depending on the level chosen when the code was made. That's how a logo can sit in the middle of some codes without breaking them.
FAQ
- What does QR code stand for?
- QR stands for 'Quick Response,' a name from its origins in the auto industry, where the codes were designed to be read very fast on a production line.
- How much information can a QR code hold?
- A lot — up to several thousand characters in theory. In practice, shorter content makes a less dense, easier-to-scan code, which is why most codes hold a short link rather than a wall of text.
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