As it is a USB device, the Arduino board might need its own drivers to be installed before your computer can talk to it.
The most recent boards, such as the Arduino Uno or the Arduino Mega 2560 board, don't need any special drivers to be installed. If you are using an older model, such as the Diecimilia board or any other board with an FTDI driver chip like the one shown in the following screenshot, you will have to install the specific drivers:
You can download the driver's version for your operating system right from the FTDI manufacturer page at http://www.ftdichip.com/Drivers/VCP.htm.
We will provide brief instructions ...