What good is virtual reality?

Isn't virtual reality a bit sad? Why would anyone want to play tennis on a computer screen when they can go out and hit a ball with a friend in the real world? Many of us already play computer games in which we pretend we're inside artificial worlds, slaying dragons, jumping off skyscrapers, and generally saving the world. Although some of these offer a kind of virtual reality, and Internet games like Second Life create an entirely artificial world, ordinary computer games do not "immerse" you in a non-existent sensory world in the same way as true VR because they do not fully take over your senses in the same way: you don't wear a headset, special gloves, and other equipment when you're playing ordinary computer games. Some computer games manufacturers have already experimented with developing their own HMDs and data gloves.

In the future, computer games are likely to take us much deeper into virtual worlds.The real applications of virtual reality are in training people to do things that are difficult or expensive for them to do in real life. For example, pilots have long trained on flight simulators because that's much cheaper and safer than having beginners go out and crash lots of airplanes. The US Airforce still trains its pilots this way, and its paratroopers practice their landings wearing HMDs and real parachute harnesses in realistic virtual simulations. NASA too has long used virtual reality to train astronauts and other space scientists. It's not easy to practice being on Mars without going there, but artificial VR simulations can help us imagine what it might be like—and get ourselves ready for meeting the real thing!