You must have seen a handheld machine at cash counters of supermarkets that a cashier uses to scan products before generating the bill. That is called a barcode scanner or barcode reader. 

Barcodes look like a series of thick and thin lines and are unique for every product. They are universally popular among sellers as they are an effective and inexpensive way of counting inventory.

A product’s details are embedded in a barcode represented in the form of varieties of bars. These are intended only for a computer to understand. A barcode scanner is enabled to read this data and automatically decode the code and its details regarding a product. These details include price, product code, vendor's name, etc. 

A computer is unable to read this directly from a barcode. Therefore, a barcode scanner is necessary as it can read and transfer this data to a computer. This device consists of three parts – a scanner, a decoder and a cable connecting the decoder to a computer.

A barcode contains details of a specific product, and this information is already stored in the system. Before the barcode system came into existence, an individual had to enter details manually, which was time-consuming and hectic. A barcode scanner has made this process much faster and also more accurate. 

A barcode scanner has a laser light which, upon focusing on the barcode given on the product, scans it. The information received in the scanner is then transmitted to the computer. This code is verified with the database of barcodes archived in the system to match the details. This whole process makes billing more efficient, and thus, all sorts of businesses use this device.

Since this system came into existence, a wide variety of types of barcodes have been manufactured. Basically, barcode scanners can be categorised as follows based on their mechanism:

• Laser Scanners: This type of scanner uses a laser beam to scan the barcode given on a product. A reciprocating mirror or a rotating prism moves the laser across a barcode to scan it. A photodiode measures the intensity of the laser light reflected on the barcode.
• Pen-type Scanners: This scanner looks like a pen and has a photodiode and a light source next to each other at the tip of the device. The cashier moves the pen across the barcode at a uniform speed, and the photodiode measures the intensity of light as reflected. The photodiode creates a waveform of the bars and spaces in the barcode. The black parts absorb the light, and the blank white spaces in between reflect it. The signal produced in this way can be entered into the system.
• CCD Scanners: These also go by the name of LED scanners. In this, hundreds of light sensors are placed in a row to measure the intensity of the reflected light. These sensors frame a voltage pattern which is similar to that of the barcode. Therefore, a CCD scanner works by measuring the light emitted from a barcode. 
• Slot Scanners: A slot scanner stays fixed in place while a user moves the barcode across for scanning through the slot. These are typically used to read identification cards.
• Camera Scanners: Camera or image-based scanners are two-dimensional scanners. They primarily use a camera and image-processing method to scan the barcode on a product.

Even though they all look similar with black-and-white images of bars of different lengths and widths, there are varieties among barcodes. The following are the different types of barcodes based on their design:

• 1D Code: Most businesses use this type of barcode. These typically have 12 characters of black-and-white gaps of various widths. These codes are only capable of carrying alphanumeric data. The length increases when you add more information.

• 2D Code: 2D codes are like QR codes or matrices and are a combination of hexagons, squares and other geometric shapes. As the name says, it is 2D, and the codes are arranged in both vertical and horizontal patterns providing 2-dimensional readability. As such, they can hold up to 100 characters and can store much more information.

• Retail Barcodes: This type of barcode mechanism uses the Universal Price Code system and is generally used for scanning products in supermarkets. Bernard Silver and Norman J Woodland invented this system. This is very useful for scanning large quantities of products.

• Non-retail Barcodes: As the name suggests, these barcodes are for non-retail purposes. You will find these in library books and membership cards.

• Pharmacy Barcodes: The use of barcodes in the pharmaceutical industry is mainly for identifying various types of drugs. These barcodes utilise the Health Industry Bar Code (HIBC) rules which identify barcodes using a "+" sign in the beginning. Each code consists of 24 characters which is a combination of letters and numbers.

• Issuing Barcodes: Bookstores and publication houses use a unique barcode system. If you go to a bookstore, you will find barcodes on books, magazines, novels, etc. These codes go by the Standard Book Number or International Standard Serial Number.

Since its development, the application of barcode and barcode scanners has seen a huge improvement. This is because businesses have benefited immensely by using this barcode. Here are some points on how businesses benefit from the barcode system:

• Depository Management: Businesses can save time and keep track more easily of their inventories, work-in-progress, file transfer status, etc. It reduces the need for manual labour and the chances of human error.
• Storehouse Management: Since storehouses have large stocks, it can get very hectic and troublesome to keep track of all these manually. A barcode scanner can be a real saviour.
• Makes Information Sharing Easier: Nowadays, you will find that many products come with a code with an option to scan from your phone. If you do, you will get information about the product, such as nutritional value, calories, etc. This also helps in spreading a business and building a good reputation.

Today, most businesses cannot function efficiently without a barcode scanner system. With this device, businesses can easily keep an inventory of their products without having to spend countless hours on them. This, in turn, has helped the barcode manufacturing industry flourish.