This document discusses mobile tagging, which links the physical world to the digital world through mobile devices. It describes how 2D barcodes called QR codes allow digital content to be accessed from anywhere by scanning the code with a mobile phone's camera. Users can generate their own barcodes and mobile websites, and various companies provide barcode readers and generators as well as expertise in mobile technologies. The overall aim is to illustrate how barcodes are essential tools for mobile internet access and to encourage further research on this topic.