I find that a lot of tourists always struggle or are intimidated by the NYC subway system, and whenever I explain it to friends and visitors, I realize that it can be a confusing system. I decided to spent some time to put together this "Absolute Beginner's Guide on How to Use the New York City Subway System" in hope that this gets into the hands of visitors before they come to this city. I hope this helps:
Minh T. Nguyen.
PS: I hope this post doesn't get removed, as this is not spam. I am not making any money from this and am just trying to help tourists.