Recreational use of marijuana is illegal in most parts of the world. The medical use of cannabis is legal in some countries, including the Czech Republic, Canada, Austria, the Netherlands, Italy and Germany. Australia is working to pass a law that will allow the use of marijuana for medical and scientific purposes. In the United States, federal law says all use of marijuana is illegal. But more than 30 states and the District of Columbia no longer arrest people for having medical marijuana, as long as they follow a state's medical marijuana rules.