EVE Online is one of the longest running, complex and impressive massively multiplayer games around. A space game with an enormous amount of freedom. You can trade, fight, join corporations of other players, and much more in a huge science fiction universe.
Eve Online is a complicated game, but it now has much better tutorials, to get you through your first few days in the game. Days? This is an MMORPG that you can play for years, and with an environment that features over 5000 star systems, you are unlikely to ever see everything it has to offer!
The star systems have three security rankings - in the safest, any aggression will result in law enforcement, while in the dangerous 'zero space' systems it's anything goes. In these systems the stakes are highest - you really can lose everything if things go wrong in EVE Online, so entering a dangerous system is very risky. If you get really involved in EVE Online, it's perhaps the best realized universes in existence. But it's not a game you can play casually.
You can get involved in some of the biggest space battles you'll ever see in Eve Online, and they look incredible. Eve Online's universe is graphically stunning, although it's possible to forget that and get lost in the details of the game! Eve Online is unique, a Space MMORPG where players have unprecedented influence over the development of the universe. If you can invest enough time into it, it's an incredible experience.