text: This is a leftover from the old, old days of computers, as in the 1980's.  Back then, a computer just had a fixed number of 'ports' that you could plug printers, modems, mice, etc. into.  USB and firewire are much much better, so most new computers don't have them, but you might see trapezoid shaped connectors with 9 or 25 little metal pins on some PCs.\n\nEach port on the computer had a name, like COM1:, PRT:, and so on.  These names referred to the hardware connections, so they couldn't be used to name a file.  For instance, one way of printing things then was just to copy a file to the printer:\n      copy file  PRT:\nCON was one of these devices...it represented the screen and keyboard.  So, you could display a file on the screen by copying it to CON:, and record keyboard input by copying CON: to a file.  \n\nIf you're comfortable in a command prompt, this still works.  Try doing\n   copy some_file CON:\nand you'll see the file contents on the screen. Try\n   copy CON: filename\nand you'll be able to type directly into a file.  Be careful, this will erase the file if it already exists. (Hit Ctrl-Z when your done).\n\nMicrosoft has a real devotion to backwards compatibility--that is, they try to make sure things that worked with old versions of Windows still work with new versions.  This is kind of taking it to extremes, since any program that uses this would be 20+ years old now.