This is a basic breakout board for the FTDI FT232RL USB to serial IC. The pin out of this board matches the FTDI cable to work with official Arduino and cloned 5V Arduino boards. The major difference with this board is that it brings out the DTR pin as opposed to the RTS pin of the FTDI cable. The DTR pin allows an Arduino target to auto-reset when a new Sketch is downloaded.
FTDI Adapter USB Controller