Bar codes first appeared in the 1970s to automate the process of pricing grocery items. Nowadays they are widely used to automate business processes as to increase productivity and reduce the chance of human error. The type of barcode used depends upon the implementation, the data to be encoded and how the data needs to be printed.

There are different types of barcode standards for different purposes called symbologies. Each symbology or barcode type is a standard that defines the printed symbol and how a scanning device reads and decodes the symbol. Several industry standards have been established and depending on the type of industry a standard needs to be implemented.

Here is an overview of some industry standards and their typical use:

Some bar code characteristics:

• CODE128: a continuous multilevel full ASCII code with three character sets.
• CODE39: an alphanumeric barcode that can encode numbers, upper case letters and a few special symbols.
• CODE39Ext: encodes the complete 128 character ASCII character set.
• DataMatrix: a high density bar code that can encode text, numbers, files and data bytes.
• EAN-13: encodes 13 digits whereby the first 2/3 digits are the country code, the next 9/10 digits are the data characters and the last digit is a checksum digit.
• EAN-8: encodes 8 digits whereby the first 2/3 digits are the country code, the next 4/5 digits are the data characters and the last digit is a checksum digit.
• Interleaved 25: a numeric only bar code.
• UPC-A: encodes a 12 digits whereby the first digit is the system character, the next 10 digits are the data characters, and the last digit is the checksum digit.
• UPC-E: a compressed bar code version which squeezes out the zeros.

Bar code scanning

Reading bar codes can easily be done with a handheld barcode scanner. A good choide is a bar code scanner that has a built-in decoders and can read several different bar code types. Most bar code scanners do not need an external power supply since they get their power from the keyboard or the USB port.

Bar code printing

Barcode fonts allow you to print barcodes from MS Windows, Mac, UNIX, AS/400 and other operating systems. You can use TrueType, OpenType, BDF, FON, PCL, PostScript (type 1) Binary and ASCII versions for most symbologies. Self-checking fonts are the easiest to use and can be entered directly from the keyboard. All barcodes require a start and stop character. You can print bar codes using bar code fonts, bar code servers, ActiveX controls, DLLs, Java beans, applets or servlets, or from within PDF documents. Optionally you can use a bar code label printer.

Bar code resources

• IDAutomation
• Barcode components
• ISBN bar codes
• UCC
• EAN