Why do I need to calibrate the system before using the pen for the first time?

• Calibration sets up the connection between your computer and the interactive pen so that you can control or interact with the image being projected from the computer. This simple process ensures that your computer can accurately detect the position of the pen on the projection surface.
  
  You need to calibrate before using the pen for the first time, or if you change the resolution on your computer or connect a different computer. You can use either pen for calibration.