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.