"For a computer, having a lot of Pi is like a human having a lot of pie: It makes it fat and slow. If you store Pi in a normal, human-readable text file (like you can create in Notepad, Emacs, vi, or whatever your favorite editor is), then Pi requires one byte per digit. So 200,000,000 digits of pi takes up 200,000,000 bytes, or 200 megabytes. Even with fast computers, it can still take a few seconds to read 200 megabytes of data from a hard disk, and a significant fraction of a second even to read through it when it's already in memory! "