Gender Changers
A problem you may encounter is having two connectors of the same gender that must be connected. You can purchase gender changers at any computer or office supply store for under $5.
Note: The parallel port on a PC uses a 25 pin female connector, which sometimes causes confusion because it looks just like a serial port except that it has the wrong gender. Both 9 and 25 pin serial ports on a PC will always have a male connector.