Yes, but it's not as efficient or cost-effective as public transportation in other parts of the world. At least in the U.S., it's severely lacking in convenience in many cities. If you're visiting a huge U.S. city like New York or Chicago, you'll have plenty of transportation options – even if you pay more than you should for them. In smaller cities and towns, it could be all but nonexistent. Consider Madison, WI (my hometown), a city of 270,000 people...without a single train. We have a poorly run bus system, and that's it. The closest train is an hour and a half drive away in Milwaukee.