The Key To Sleep uses blue L.E.D.s (light emitting diodes) and binaural beats (sounds) that pulse at specified frequencies. Each Key To Sleep system gently guides the user from Beta the wide-awake state then into the more relaxed brainwave state of Alpha and then into Theta the best state for learning. The process is very similar to the cycle of sleep you enter into each night. Each device is like a mini computer, which stores the audio recordings, (guided creative visualizations) and then plays back your selection. The device is encoded to play only the user's programs. If your "KEY TO SLEEP" is damaged all of your programs are easily replaced on to your new machine. Your data is always available to you on your own personal file manager.