What are Bar Codes ?
Bar codes are simply machine-readable print. They allow printed information to be directly read into an instrument or computer to automate the processes of identification and tracking. One-dimensional bar codes are composed of a series of vertical lines and spaces that encode numbers, letters and additional information that helps bar code readers to verify the accuracy of their readings (error checking). Typically only one short line of information can be encoded and is usually a unique ID number.

Two-dimensional bar codes can be composed of a square field of small dots or a rectangular field
of what look like stacked 1-D bar codes. They can contain up to an average
paragraph's worth of information such as name, address, phone number and brief
medical history. They also can be read accurately, even when a significant
portion of the code is obscured or damaged.


Bar Code Formats

There are a number of 1-D bar code formats. Many
were designed for specific applications, but a few were designed for general
use. The format that we recommend for general use is called Code 128. Code 128
is compact, codes for all of the ASCII characters (upper & lower case
letters, numbers and punctuation symbols) and has sophisticated error checking
features. An example of Code 128:

A few other 1-D formats:Code 39- The "old" general use code.
In wide use, but not as compact or accurate as Code 128.

UPC- Retail product code used in US. Identifies product and package size via a unique ID number.

Postnet- Used to encode Zip codes on US mail.

There are three major 2-D bar code formats. PDF-417, DataMatrix and MaxiCode. PDF-417 and DataMatrix are
available for general use, while MaxiCode was developed by UPS for tracking their packages. An example of PDF-417:

Bar Code Printing

The easiest way to use bar codes is to print
them on self-adhesive labels and apply them to items that need to be identified
or tracked. Labels can be made of paper, vinyl or polyester. Paper labels are
fine for temporary labeling of indoor items in a controlled environment, but
vinyl or polyester labels are necessary for permanent labeling or for use in
wet, outdoor or otherwise harsh environments. Printing is generally accomplished
with thermal, thermal transfer or laser printers. Thermal printers use
heat-sensitive label material that darkens where it is heated. These labels are
only suitable for temporary use because they will fade with time and heat and
are only available in paper. Thermal transfer printers heat an ink-coated ribbon
which then transfers the ink to the label material. They can print on any
material, but a specialized printer is required, along with a specific Windows
printer driver. Laser printers can print on paper or polyester and with
polyester, can produce a sharp and permanent label, since the toner is burned
into the label material and is waterproof. Label material must be specially
formulated for laser printers so that the adhesive doesn't melt and ooze into
the printer mechanism. Bar codes can also be incorporated directly into
documents by generating them in a label program like LabelWorks and copying and
pasting them into a document. Programs like SpeedBar run in the background and
allow bar codes to be automatically incorporated into documents wherever
specific symbols are typed in the
document.


Bar Code Scanners

Scanners for 1-D bar codes can be in the form of
wands, CCD guns or laser guns. Wands and the least expensive, but to read, they
must be in physical contact with the bar code and guided straight across the
code. They are best suited for low-volume scanning. CCD guns must be close, but
don't have to contact the code to read it. They are less expensive than laser
scanners, but can't read as far away or as wide a code as laser scanners. Laser
scanners emit a red guide line that assures the gun is aligned with the code,
and can read it properly, from a few inches to a few feet away, in some cases.
Most scanners require a decoder to convert the scanned information into ASCII
code that a computer can use. Fixed scanners and their decoders are connected
directly between the keyboard of a computer and the CPU. They place the scanned
information wherever the blinking cursor happens to be, as though it was typed
in. Portable scanners are attached to a portable decoder that also stores the
data and the programs used to scan and upload. After scanning is complete, the
data is transferred from the portable decoder (or reader) via a cable to
computer keyboard port. The portable reader uploads the data and executes
programmed keystrokes so the data can be properly located in the application
running on the computer. Again, it is uploaded as though someone is typing it in
from a keyboard.


Bar Code Tracking

UPC bar codes are used to identify, price and
update the inventory of retail goods. Postnet and MaxiCode are used to sort and
track packages in shipment. Many of the remaining codes, such as 39 or 128 are
simply used to automatically capture data about assets or inventory.

Benefits through the supply chain For the manufacturer, distributor,
wholesaler and customer. · Fast and accurate data capture at every point in the
supply chain, including goods receiving, warehousing, picking, despatch and
point of sale. · Better, more timely, management information. · Less
stock-holding and less waste. · Greater responsiveness to trade customers and to
consumers. · The ability to automate warehousing. · Better control over
distribution and storage. · Fewer errors in the recognition of goods. · Improved
company to company communications throughout the supply chain. · One standard
for use with all trading partners and therefore no conflicting demands.

We provide barcode labels and bar code solutions where durable moisture, heat and
solvent resistant bar code labeling is needed. Consecutively numbered paper,
polyester, polyimide and other plastic labels are provided for many uses.
Medical, pharmaceutical, electronics, warehouse, library and industrial
applications are supported. Blank labels are provided for thermal transfer and
laser printers. Bar code label printing and tracking systems are available to
address many areas.