Capacitive touch sensing works by detecting when a person (or animal) has touched one of the sensor electrodes. The shield has 12 'figure 8' holes in it that can be gripped onto with alligator clip cables. Attach one side of the clip to the shield and the other side to something electrically conductive (like metal) or full of water (like vegetables or fruit!); each connected item effectively becomes a touch sensor. These items can then be read by the Arduino and used as inputs to create all sorts of interesting input devices!

The shield works great with any Arduino and only requires the two I2C pins (SCL & SDA) to operate. Adafruit's MPR121 12 Key breakout tutorial can be used to help get this shield up and running as it uses the exact same chip.