Or, in human terms, you can eventually find your car in a 2D parking lot, but not a 3D parking garage (as per Seinfeld http://en.wikipedia.org/wiki/The_Parking_

Or, in human terms, you can eventually find your car in a 2D parking lot, but not a 3D parking garage (as per Seinfeld http://en.wikipedia.org/wiki/The_Parking_Garage http://en.wikipedia.org/wiki/The_Parking_Garage)