What is a barcode/QR code?

It is a machine-readable optical label, containing information about the item to which it is attached. The information is arranged in a specific way, and it is unique to the item. Barcode/QR code is a new form of data storage, and is used in many fields, from manufacturing and commerce to medicine and biology.

It can be scanned by a barcode reader, which can decode the information and show it to the user. It can also be scanned by a mobile phone, which uses the barcode reader to do the scanning. The information that is scanned is saved in a database, and it is possible to search for it later.