How Barcodes Work

Don't be intimidated by barcodes. You don't need to be a rocket scientist to understand them; they are just a different way of encoding numbers and letters by using a combination of bars and spaces of varying widths. Think of them as another way of writing since they replace key-data entry as a method of gathering data. In business, the correct use of barcodes can reduce inefficiecies and improve a company's productivity thereby growing their bottom line.

Simply put, barcodes are a fast, easy, and accurate way of entering data.

This may come as a suprise tu you! A barcode doesn't contain descriptive data. Just as your social security number doesn't contain your name or address, a barcode is also a reference number that a computer uses to look up an associated record that contains descriptive data and other important information.

For example: a barcode found on a loaf of bread doesn't contain the product name, type of bread, or price; instead it contains a 12-digit product number. Now, when this number is sacnned by the cashier at the check-outi it's transmitted to the store's computer which finds the record associated with that item number in its database. The matching item record contains a description of the product, vendor name, price, quantity-on-hand, etc. The computer instantly does a "price lookup" and displays the price on the cash register. (it also subtracst the quantity purchased from the quantity-on-hand.) This entire transaction is done instantly; think of how long it would take the cashier to key in a 12-digit number for every item you wanted to buy!

To recap: a barcode typically has ID data encoded in it, and that data is used by a computer to look up all specific information associated with the data.

Symbology: An easy definition

Symbology is considered a language in barcode technology. Just as you might speak French while traveling in France, a symbology allows a scanner and a barcode to "speak" to each other. When a barcode is scanned, it's the symbology that enables the information to be read accurately. And then when a barcode is printed, it's the symbology that allows the printer to understand the information that needs to be turned into a label.

Barcodes are read by sweeping a small spot of light across the printed barcode symbol. Your eyes onlu see a thin red line emitted from the laser scanner. But what's happening is that the scanner's light source is being absorbed by the dark bars and reflected light and converts it into an electrical signal.

The scanner's laser (light source) starts to read the barcode at a white space (the quiet zone) before the first bar and continues passing by the last bar, ending in the white space which follows it. Because a barcode cannot be read if the easy to keep the sweep within the barcode area. The longer the information to be caded, the longer the barcode needed. And as the length increases, so does the height of the bars and spaces to be read.

There are three basic types of barcode scanners-fixed, portable batch, and portable wireless.

Fixed scanners (hand held or mounted) remain attached to their host computer or terminal, and transmit one data item at a time as the barcode is scanned.

Portable batch scanners are battery operated ans store data in memory for later batch transfer to a host computer.

Wireless portable scanners also store data in memory, however data is transmitted to the host in real time. This allows for instants access to all data for management decisions.