THE 2-MINUTE RULE FOR ACGWIN

The Cygwin DLL has a console driver that emulates a Unix-fashion terminal in the Home windows console. Cygwin's default user interface could be the bash shell running from the Cygwin console. The DLL also implements pseudo terminal (pty) devices. Cygwin ships with several terminal emulators that happen to be according to them, like mintty, rxvt/urx