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What Is a Barcode Reader?

Jacob Queen
Jacob Queen

Barcodes consisting of black lines with spaces between them are often used to keep track of inventory and simplify other aspects of running certain businesses, especially grocery stores and other places where complex tracking is necessary. A barcode reader provides a quick way to translate the codes, and using one requires very little effort on the part of workers. Barcodes represent numbers that can be linked to items in a database, and the readers have an ability to measure light reflections, allowing them to pick up the barcodes off the surfaces of packaging. Most barcode readers are shaped either like a gun or a pen, but some are set up in fixed positions.

Prior to the invention of barcodes and the barcode reader, grocery stores and other kinds of shops had much more difficulty keeping track of inventory, relying more heavily on manual methods. Knowing exactly how many items are available in a store is often crucial for retailers because it allows them to keep a tally of how well things are selling and simplifies the process of making decisions about quantity when making another order. Typically, a barcode reader is set up at each cash register, connected to a computerized database with information on all the items in the store. When the clerk scans items during a purchase, the system registers the sold item in the database, keeping a real-time inventory estimate.

A barcode reader.
A barcode reader.

Barcodes are always made up of black lines because of the way readers work. Since black surfaces are typically known to absorb more light and brighter surfaces are more reflective, bouncing light off a barcode generates a simple pattern of spaces and lines that can be registered with relatively simple equipment. The actual technology used in barcode readers has changed over time, including the use of lasers, light emitting diodes (LEDs), and even actual cameras with the ability to pick up codes from a greater distance or read multiple codes simultaneously.

A handheld laser barcode scanner.
A handheld laser barcode scanner.

The form factor for a barcode reader is often dependent on its use. Many are designed so that clerks and other operators can maneuver them for easier access to barcodes, and these are often shaped a lot like guns or pens. Others are set up so that they remain stationary and the barcode is moved into a position where the scanner can read it, including the kind that are set up inside the conveyer belt tables in some grocery stores.

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Discussion Comments


@Mykol: you had to manually input the price of everything? Wow, then barcode reader really did a great help.


When I worked in retail and we would have inventory, using a barcode reader scanner was so much easier than the old way of doing inventory.

Whenever you use electronic equipment, you still have your glitches and frustrating times when the reader won't work right. I consider these setbacks minor in comparison to the amount of work they save in the long run.

Accuracy is another thing that is greatly improved with barcode readers. As long as the information is entered in the system correctly, you have much more accuracy.

Of course, human workers are also those who are inputting the information in the system, so there is always room for error. Overall though, barcode readers have made selling retail products much more efficient.


I worked in retail when I was in college, and this was before scanner barcode readers were used.

I had to manually input the price of everything. The one good thing was the register told me how much change to give back so I didn't have to count back every penny in change.

There have been many changes since then and I imagine that barcode readers have simplified the whole process quite a bit.

These would also save a lot of time since it is all computerized. Before using barcode readers, every item had to be individually priced, which took a lot of time.


@starrynight - It seems like there is more to operating a barcode reader than you would think!

I think the barcode readers that are shaped like a gun are the most convenient. I like that I can leave heavy items in my cart and the cashier can just use the portable reader to scan it. Definitely more convenient for the customer and the employee!


Barcode readers are very handy. I can't imagine having to stand and wait for the cashier to manually enter the price of all my groceries before I could check out. I think that would be very annoying.

Also though, barcode scanners don't always work that well. I'm a big fan of the self checkout in grocery stores, and I've noticed that sometimes I have trouble getting the scanner to scan my items.

Also, if you go to fast barcode readers seem to stop working. Once my boyfriend and I were buying groceries and we kept putting stuff on the conveyor belt we thought we scanned but the reader hadn't picked up! We were getting really frustrated and finally one of the employees came over and let us know we were going too quickly! We had much more luck once we slowed down.

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    • A barcode reader.
      By: Kuruan
      A barcode reader.
    • A handheld laser barcode scanner.
      By: mrkob
      A handheld laser barcode scanner.
    • Barcode readers are commonly employed at grocery stores to make checking out go more quickly.
      By: Monkey Business
      Barcode readers are commonly employed at grocery stores to make checking out go more quickly.