text: Emissions and greenhouse gases have been a problem in modern society due to the fact that almost everyone has an automobile. This has been creating a large amount of stress on the enviroment and can lead to problems in the near future. Because of these problems, many enviomental agencies have started regulating car usage to try to keep the enviroment safe. Some of the ways they are doing this include promoting "car reduced" communities, which rely more on public transportation serving the suburbs than personal transportation. This helps to cut down on traffic and in turn the amount of emissions produced by cars on the road. Another way to prevent this is to ban the act of driving all together. Paris has done this in the past to combat the amount of smog accumulating in their city by banning the driving of certain license plate numbers which reduced the amount of traffic and emissions.