There are a large number of different types of barcodes. Think of barcodes as spoken languages, each one different from the others. Every barcode type is designed to do something special. Different types of barcodes are known as barcode symbologies.

You can break barcodes down into two different major groups: linear / one dimensional barcodes, and two dimensional barcodes. Two dimensional barcodes can pack a lot of data into a small space, but most inexpensive barcode scanners will not read them.

So if you need a bar code that is easy to print and can be read by virtually any scanner, you need a linear or one dimensional bar code. A linear bar code is composed of bars and spaces all in a single line. Linear bar codes can not hold a lot of data- typically no more than about 9 data characters for every inch of horizontal barcode space.

So what are the major types of linear barcodes and how do you choose the right one? A good web site that will help you pick the type of barcode you need is whichbarcode.com. They feature an interactive quiz that helps you select the right barcode. The major types of barcodes include:

• Bar Code 2/5 Interleaved- includes numbers only and you must use an even number of digits, optional checksum, variable length, may use bearer bars to prevent misreads, also handles ITF-14 barcodes.
• Bar Code 3/9- includes numbers, upper case letters, and a few special characters, optional checksum, variable length, Full ASCII mode possible with some barcode readers (at reduced density), often used by the DoD.
• Bar Code 93- includes numbers, upper case letters, and a few special characters, two required checksums, variable length, Full ASCII mode integrated into the barcode (at reduced density).
• Bar Code 128- includes all ASCII characters and offers a separate high density numeric mode, required checksum, variable length, also handles UCC/EAN 128, SCC-14, SSCC-18, and many other variants.
• Bookland- a special EAN 13 barcode with supplemental data used to turn ISBN book numbers into book barcodes with optional pricing information.
• Codabar- includes numbers and four letters which are used as the Start and Stop codes, used by libraries and blood banks.
• EAN 8- a fixed length 8 digit numeric bar code.
• EAN 13- a fixed length 13 digit numeric barcode used on retail products in Europe. All numbers are assigned by the EAN International.
• PostNet- a numeric bar code used by the US post office to route mail.
• UPC-A- a fixed length 12 digit numeric bar code used on all retail products in North America. All numbers are assigned by the Uniform Code Council.