QR codes, developed by a Japanese company, have been around for over fifteen years. With the advent of smart and Web capable mobile devices, we witness a steady growth of interesting commercial applications using QR codes. As the movement of using QR codes in education is still in its infancy, this paper serves to be one of the first comprehensive papers in journal publication to fully delineate (a) the user characteristics of QR codes, (b) the processes of making and reading QR codes, (c) the survey of commercial applications using QR codes, (d) the literature review of educational applications using QR codes, and (e) offer suggestions and implementations of QR codes in school education.