A bar code is "[a] series of rectangular marks and spaces in a planned pattern."
A bar code is
|“||[t]he set of vertical bars of irregular widths representing coded information placed on consumer products and other items (such as identification cards) that may require this type of identification.||”|
It is a code representing characters by sets of parallel bars of varying thickness and separation that are read optically by transverse scanning. The most common application of bar code technology is the Universal Product Code (UPC), which has been used for several decades on consumer product labels.
There are two types of bar codes:
- Linear barcodes — are a series of lines and spaces can be read by a scanner using a moving laser beam (or laser pattern) or other image capture technology.
- 2D barcodes — allows the encoding of more data in a smaller space that a linear barcode. This form requires special equipment to implement, therefore making it less popular.