Web changes everything and GIS is no exception.Often the terms Web GIS and Web Mapping are used synonymously, even if they don't mean exactly the same. In fact, the border between web maps and web GIS is blurry. Web GIS, as the combination of the Web technology and geographic Information System (GIS, has grown into a rapidly developing discipline since its start in 1993. The Web unlocked the power of GIS, from offices to laboratories. It has put GIS in the homes of millions and in the hands of billions, and made it usable across all industries, from government and business to education and research. Web GIS is extremely powerful because 80% of everything that we do is based on location. There are absolutely no limits to what can be done using GIS. Web GIS allows us to view, understand, question, interpret, and visualize data in many ways that reveal relationships, patterns, and trends in the form of maps, globes, reports, and charts. It helps us answer questions and solve problems by looking at data in a way that is quickly understood and easily shared. Finally, it can be integrated into any enterprise information system framework.