[David] is here to help with his isolated versatile FTDI circuit ... that might have been a parallel or serial port. Today it’s almost always USB, specifically serial over USB.

[Johan von Konow] found that he was using an FTDI USB-to-Serial chip in a lot of his projects ... The copper fingers are designed to plug into your USB port. And if you’ve got an unused thumb ...

Add or Remove Programs entry for FTDI USB Serial Converter Drivers. This is a driver pack that allows USB ports to be used to connect to Serial bus devices with a USB - Serial adapter cable.