This article systematically explains what a 2D barcode is, the technical differences and application scenarios between 1D and 2D barcodes, and provides a detailed comparison of key metrics such as data capacity, error correction capability, and spatial efficiency. Through practical cases, it outlines the key points for selecting barcode scanners, helping professionals in logistics, retail, healthcare, and other industries choose the right barcode solutions based on their business needs to improve data management accuracy and work efficiency.