The primary use of QR codes in modern technology is to store and quickly share information. Scanned using a smartphone camera, QR codes can link to websites, provide contact details, or convey various types of data. Their ability to store a significant amount of information in a compact format makes them useful for marketing, payments, and authentication purposes. QR codes have gained popularity due to their efficiency in bridging the gap between physical and digital content, making information accessible with just a scan.