EVE Online is an open-ended Massively Multiplayer Online Game
EVE Online is an open-ended Massively Multiplayer Online Game (MMOG). Most other MMORPGs focus on a structured playing style with predictable outcomes and monotonous leveling. This seemingly innocent fact is why EVE is so different from almost all other MMORPGs, as the players have an incredible impact on how the game develops.
One could compare this to the difference between a playground, such as EVE, and a theme park, which would be the traditional MMOG. In a playground you have access to different kinds of toys and rides, and you are allowed to use your own imagination to figure out how to create games you enjoy. In a theme park all the rides have been created for you and are either good or bad by design. The playground clearly offers more freedom but it requires you to think and be an active participant, while the theme park has taken those responsibilities away from you and you can just go with the flow. As an interesting side-note, "theme park" style MMORPGs commonly develop lines, just like real world theme parks, as players wait for monster spawns, rare items, or quest requirements.
Players that enjoy the freedom and opportunities for creative thinking an open-ended game offers have become mesmerized by EVE, while others that depend on structured, repetitive game style have not. For this reason we don't contend that EVE is for everyone, but for those that enjoy a bit more of a challenge.
A unique aspect of EVE is that it is run on one server. In EVE you can find over 25,000 players at any given time interacting in the same persistent universe. Other MMORPGS are played on multiple servers called Shards; these have a limited number of players on each, usually between 500 and 3000.
The bottom line is that EVE is a rich and immersive universe centered on human interaction. Players can play the game as a simple space trader or endeavor to control the largest, most powerful company in the universe. We provide the rules and tools, but it is the players themselves who create the adventures.