Games versus Worlds: How Some Massively Multiplayer Games Differ from Others
At first glance, this may seem like a strange topic. After all, MMGs are all games, right? Well, yes and no.
Many MMGs are designed as purely games for gaming's sake. World of Warcraft is an excellent example of this; you are cast as a fantasy hero who solves hundreds of quests and becomes, over time, very powerful, capable of slaying fiery elementals and huge dragons. This is very much like a regular computer game, except for the fact that you're playing with thousands of other people.
Other MMGs, though, have a different aim. They give you the tools to "live" within a virtual world. You have more tools to make your own mark on the world, such as building your own home, turning it into a storefront to sell the goods that you make to other players, or simply spending time talking to friends. Although virtual worlds have many of the same elements as "game" MMGs, such as fighting monsters, these elements generally aren't the main focus of the game. Star Wars Galaxies is an excellent example of a virtual world; in this game, there are very few nonplayer characters (computer-controlled characters) and almost every piece of equipment that players use in the game has been created by another player.
Another important feature of virtual worlds is a style of game play known as player vs. player (sometimes shortened to PvP or PK) or realm vs. realm (RvR). Games with a PvP component allow players to attack one another. In some games, such as Dark Age of Camelot or Shadowbane, the entire game is built around the battles between players. Other games, such as EverQuest, have almost no PvP combat at all.
What does this have to do with the games versus worlds discussion? Well, worlds tend to have more open player vs. player combat, simply because the freedom of characters to kill one another is often seen as part of the freedom to live in a virtual world in general. Ultima Online, the first virtual world MMG, allowed PvP combat with almost no restrictions whatsoever after players left the starting cities. The plan of the game designers was for players to create their own rules, so that a civilization of sorts would develop. The "civilization" that developed was, well, survival of the fittest, which was great fun for the fittest and not much fun for everyone else. Games that came later tended to have stricter controls on who could do what to whom. Still, a hallmark of a virtual world is the characters' ability to do ill to one another; after all, it's difficult to play a villain if the game forces you to be nice all the time. If you are leery of the ability of other players to harm your character (whether through a bad experience in an earlier game, or simply from a realistic appraisal of human nature), this is something you should definitely find out about before getting very far into the game.
In general, every MMG is both a game and a virtual world, and the nature of any game is determined by what percentage of each the MMG has. Games with very little virtual world content are almost entirely dependent on the game's developers to add things to do. This can be a vicious cycle, because millions of players will churn through the game's attractions far faster than any game company can hope to create them. Most MMGs release an expansion once a year (or sometimes more often than that) that adds more content — literally, adds more game — for the players to explore. Virtual worlds, however, have a leg up on the competition in that the players themselves are partners in creating the game's content. If the game gives players tools to create empires and battle one another for dominance, the players themselves become the storytellers, instead of the game designers. Some people aren't terribly attracted to this idea ("I'm paying other people to entertain me, not to do the job myself!"), but for others, this is the aspect of the game that keeps them playing years after the game has been released.
Really, the only person who can determine the proper balance is you. If you're more into playing a game with other people, and being entertained and having adventures, look for a "game" MMG. If you are more attracted to freedom of action and the ability to make your own mark on the world that you can't find in other games, then look for a "virtual world" MMG.