The Virtual Boy was a portable gaming system that wasn’t very popular. In fact it was so unpopular that it never had a European release and never made an appearance in the UK. As a result only 22 games were released for the system. The Virtual Boy used red LED lights to produce 3-D graphics. The use of red LED lights was chosen because they were the least expensive LEDs at the time. During development of the system a LCD screen was used but found to be too blurry at the time and dropped from the system. The Virtual Boy runs on 6 AA batteries that slot into the back of the controller and can also be used with a separately sold AC Adapter. The system is portable but has to be used on a flat surface to be playable. The Virtual Boy frequently reminds players to take breaks during game play to avoid headaches and other side effects of playing for too long with the system. The System has an Extension Port but no games ever used it due to the Virtual Boy being discontinued in 1996 only shortly after being released in 1995. The Virtual Boy was a huge disappointment for Nintendo and is the only console developed by the company to be a failure. Nintendo shipped around 800,000 Virtual Boy Consoles during its lifetime.