One of the relatively newer genres in the gaming industry is the MMORPG. It's advent goes back to as far as the 1990s when games such as Ultima Online and EverQuest popularized the concept of an online gaming community where people can band together and bash random critters for experience and gold.
One of the most popular MMORPGs to date is Blizzard's phenomenal World of Warcraft, which has a subscriber count of at least 8.5 million worldwide. However, it owes a lot of its existence to its proverbial forefathers. Conditions back then were considerably different for such a budding game genre to grow.