Delphi/Pascal "PORT" Array Question

I'm looking for info. on the "port" predefined array which allows you to
directly read and write to certain memory locations using this array.
More specifically, I'm looking for a way to write characters to the
printer port directly using the port command. Please respond with help
or advice. Thanks in advance.
                                        -Sid

P.S. Absolutely no help from Delphi's Help files. All I need to know is
exactly what the array represents.