often included as barcodes, these do not use bars as linear barcodes do. These can be read using purpose-built 2D optical scanners.

Both matrix codes and linear barcodes can also be read by a digital camera connected to a computer. After a photograph of the barcode is taken, software is used to analyze the image to deconstruct and decode the code. A mobile device with a built-in camera, such as a smartphone, can function as this type of barcode reader using specialized