QR codes were invented in 1994 by Toyota to track vehicles during manufacturing. They allow for high speed decoding of large amounts of data. While initially used in automotive manufacturing, QR codes are now commonly used in advertising and product packaging. QR codes can store various data types including numeric, alphanumeric, byte and Kanji characters. The size and data capacity of the QR code depends on its version number, with larger versions having more data capacity. QR codes are easily generated and scanned using free online tools and mobile apps, allowing for fast transfer of information to online servers.