When you live in a city like New York or Chicago, it's fairly easy to find your way around. For the most part, urban planners patterned these cities on a grid with numbered streets indicating one direction (East/West) and avenues or named streets indicating the perpendicular other (North/South). So if you're at my favorite Mexican restaurant in the East Village and want to get to my favorite all-veg diner in the Lower East Side, you can do so with ease simply by knowing the cross streets.