Here is some information that will give you a basic introduction to barcodes. If you need more details about particular barcodes, check out our page on different types of barcodes. And we are always happy to answer questions; just email us at firstname.lastname@example.org.
2-Dimensional symbols are generally square or rectangular patterns that encode data in two
dimensions. They fall into two general categories: 'Stacked
barcodes' are constructed like a layer cake of barcodes stacked one on top of
the other; they can be read by special 2-D scanners or by many CCD and laser
scanners with the aid of special decoding software. 'Matrix Codes' are
built on a true 2-D matrix; they are usually more compact than a stacked
barcode, and they can be read only by a true 2-D scanner (imager). The primary
advantage of 2-D codes is the ability to encode a lot of information in a
Widely-used 2D codes include DataMatrix (pictured above), PDF-417, and the QR Code.
The practical limit for a standard linear barcode depends on a number of factors, but 20 to 25 characters is an approximate maximum. All-numeric data takes less space than mixed alpha-nuumeric data. 2D symbols can encode up to as many as 2,000 characters.