Answer: Bar codes
Explanation:
A barcode is a way of representing data in a machine-readable and visual form. In the past, barcodes illustrated data by placing the parallel lines at intervals and altering the widths. Nowadays, barcodes known as one-dimensional (1D) or linear are scanned by optical scanners. Also, the two-dimensional (2D) barcodes were manufactured using dots, rectangles, hexagons and some geometric patterns, known as matrix barcodes. Barcodes are used for the tracking of products.