A barcode labelis an optical machine-readablerepresentation of data relating to the object to which it is attached. Originally barcodes represented data by varying the widths and spacings of parallel lines, and may be referred to as linear or one-dimensional (1D). Later they evolved into rectangles, dots, hexagonsand other geometric patterns in two dimensions (2D). Although 2D systems use a variety of symbols, they are generally referred to as barcodes as well. Barcodes originally were scanned by special optical scannerscalled barcode readers; later, scanners and interpretive software became available on devices including desktop printersand smartphones.

The first use of barcodes was to label railroad cars, but they were not commercially successful until they were used to automate supermarketcheckoutsystems, a task for which they have become almost universal. Their use has spread to many other tasks that are generically referred to as automatic identification and data capture(AIDC). The equipment of producing barcode labels in Sinicline are all advance and being managed by experienced workers.

Other systems have made inroads in the AIDC market, but the simplicity, universality and low cost of barcode labelshas limited the role of these other systems until the first decade of the 21st century, over 40 years after the introduction of the commercial barcode, with the introduction of technologies such as radio frequency identification, or RFID.