This is a great and relatively easy and quick way to communicate for people who can't move their limbs, but their eyes can still move. It is very good if the power (electricity) goes out, or if the "patient" can't always have a computer right in front of them. For me, (Jason Becker) no computer system works close to as fast as this, especially once you and your caregiver memorize it. It is also better for me because staring at a computer zaps my energy and makes my eyes weak and tired. The human interaction is also very nice.