The size of a postcard or the size of Manhattan?

TODAY I READ this about 32 and 64 bit Cpu differences. Cool.

4.3 billion times bigger. To grasp the enormous leap from 32-bit to 64-bit processing, imagine equating the range of numbers a processor can express with a two-dimensional area. A 32-bit processor can express a range of integers equal to the size of a postcard, while a 64-bit processor can express a range of integers larger than the island of Manhattan.