What is a barcode?
A barcode is a machine-readable code generated in the form of numbers and parallel lines of different widths; they help identify products. Different countries and industries use varying templates to print barcodes on products to meet their specific requirements.
Barcodes started with a simple one-dimensional design with basic black lines; today, they come in several shapes and sizes.
Barcode software keeps track of product locations, stock levels, and raw materials. It automates the data entry process and reduces potential human error.
Manufacturers and other e-commerce businesses use product information to make data-driven business decisions and improve productivity and efficiency. The lines and patterns on a barcode allow basic information about the product to be easily read by the scanning device and automatically entered into a computer system or database.
This reduces the time taken to record product information manually. Some barcode software also has features to generate or scan radio frequency identification (RFID) tags for asset tracking.
Types of barcodes
Out of the multiple types of barcodes available, universal product codes (UPCs) are one of the most commonly used. UPCs are used for labeling almost every retail product in the US market. Each product has a unique UPC to identify it.
Broadly, two main categories of barcode systems are in use today: 1-dimensional barcode and 2-dimensional barcode.
1D barcodes are a series of black and white bars that store product type, color, and size information. Examples include UPC, European Article Number (EAN), Code 39, and Code 128.
2D barcodes are more complex. It can display inventory levels, product images, and prices. While not all readers can scan a 2D barcode, several wireless barcode scanners support 2D. Examples include quick response (QR) codes and data matrix codes.
Learn more about the types of barcodes:
- Code 39: Code 39 got its name because it could encode nearly 39 characters in its barcode. However, that number has now increased to 43. It allows both digits (0-9) and characters (A-Z) and is commonly used in the United States Department of Defense.
- Code128: Code128 encodes all characters of the American Standard Code for Information Interchange (ASCII) 128-character set, including numbers, symbols, and punctuation marks. It’s a powerful barcode that stores information and data for transport, logistics, and distribution.
- GS1 Databar: A Global Standard 1 (GS1) Databar can represent data in a smaller area when compared to existing barcodes. With the help of application identifiers (AIs), GS1 Databars reveal information like expiration dates, product attributes, and lot numbers. Labeling GS1 Databar symbols on all ethical pharmaceuticals is mandatory as of 2015.
- EAN-13 and EAN-8: European article number barcodes (EANs) are typically found outside the United States and displayed on consumer products such as shoes, groceries, and clothes. The EAN-13 has thirteen digits, whereas the EAN-8 has eight digits. EAN-8 is helpful for products that have a small label space, like candy.
- ITF-14: The Interleaved Two of Five (ITF-14) barcode uses a 14 digital number that can deal with high printing tolerances and is especially useful if it needs to be printed on cardboard. It is typically used for products that may not require any point of sale (POS) interaction.
- Codabar: Codabar is an easy-to-print, self-checking barcode symbol used in photo labs and FedEx bills. It can encode up to 16 characters using consecutive numbers without a computer. It registers inaccurate data as a wrong scan and helps reduce scanning errors.
- QR code: Invented in 1994, QR codes store information as a series of pixels in a square-shaped grid. Any digital device can easily read QR codes without a specific scanner. It contains arbitrary information and is often used as a label.
Barcode components
A barcode is typically made up of three main components.
- The quiet zone (margin) is the black margin at both ends of a barcode. If the width of the margin is insufficient, a barcode is difficult to read. The distance between the outermost bar of one barcode and the outermost bar of another is 2.5mm.
- Start and stop characters represent the start and end of the data. These characters may vary depending on the type of barcode.
- The check digit (symbol check) helps make sure the encoded data is correct.
How barcodes work
The width of the black bars represents the numbers 0 or 1, while the sequence of these bars signifies numbers between 0 and 9. A computer connected to the barcode reader contains information about these bars and spaces and the associated data.
The stored data may vary in different settings. In a warehouse, the barcode might encode the item’s color, size, and other attributes that help understand a detailed view of the current inventory and quickly fulfill orders, helping with efficient warehouse management.
In a retail store, this information could look like the check-out price, product name, and size of the clothing item. Businesses use this to track products through the product life cycle from the manufacturer and distributor to purchase, service, and repairs.
How to scan barcodes
Barcodes are easy to work with and don’t require any technical know-how or additional training. Learn how to scan barcodes on scanners, iPhones, and Androids.
The process of scanning a barcode may vary depending on the device. However, most scanners are easy and only require the below three steps. Some may come with a button, and some may not.
- Aim the scanner’s red laser at the desired barcode.
- Press the scanners button (if necessary). If not, swipe the barcode across the flat surface of the scanner.
- If scanned correctly, the scanner makes a beep.
When using an iPhone, a specific mobile application is required. To scan barcodes on iPhone:
- Install a barcode scanner application on the iPhone.
- Follow the sign-up instructions on the application.
- Find the code to be scanned and point the camera at the barcode.
- The barcode is immediately scanned once the scanner is centered and displays the required information.
The steps to scan a barcode are similar on Android since smartphones don’t have a barcode reader installed. To scan barcodes on Android:
- Install a barcode scanner application on the device.
- Follow the sign-up instructions on the application.
- Find the code to be scanned and point the camera at the barcode.
- The barcode is immediately scanned once the scanner is centered and displays the required information.
Benefits of barcodes
Barcodes help encode product information that organizations use for data-driven decisions. This information helps improve inventory tracking and increases accuracy, invoicing, and cost savings. A barcode inventory system speeds up the sales process and optimizes operations. Some additional benefits are:
- Improved accuracy. With the help of a barcode scanner, businesses keep better track of inventory and sales when compared to manual data entry, which is prone to human error.
- Real-time data. Data about inventory levels and sales are available immediately due to the quick information processing.
- Reduced training requirements. Scanning a barcode is as easy as pointing and clicking.
- Better inventory management. Due to the availability of real-time data and improved accuracy, businesses have a better sense of inventory turnover and management of products, raw materials, and transport.
- Low cost of implementation. Generating barcodes and obtaining a barcode reader is quick and simple, potentially saving implementation costs and improving transaction speeds.
Barcode vs. QR code
A barcode reader and QR code are systems that store various information related to products. A barcode is a traditional printed machine-readable data representation with black parallel lines and spaces of different widths.
A QR code comprises black and white modules arranged in a square pattern and typically stores more data than a barcode. QR codes don’t require a special barcode reader.
A barcode contains information only in a horizontal direction; a QR code contains horizontal and vertical information. QR codes are more versatile than barcodes and can hold information like digital payment methods, event ticketing, or food delivery.
A barcode tool integrated with inventory management software can help track essential data such as product location, stock level, or raw materials.

Tanuja Bahirat
Tanuja Bahirat is a content marketing specialist at G2. She has over three years of work experience in the content marketing space and has previously worked with the ed-tech sector. She specializes in the IT security persona, writing on topics such as DDoS protection, DNS security, and IoT security solutions to provide meaningful information to readers. Outside work, she can be found cafe hopping or exploring ways to work on health and fitness. Connect with her on LinkedIn.