Runescape was developed back in 1999 and is run by the parent company, Jagex Ltd. It boasts a player population of over 1,000,000 users. Runescape prides itself on not only being an online game (Runescape Gold) of adventure and quests, but also teaches kids about economics, boosts their thinking skills, and emphasizes teamwork to get jobs done.
As with almost any online gaming, you can play Runescape as a non-member for free or buy a membership. Being a member, of course, entitles you to more opportunities to succeed at the game. Non-members enjoy a fulfilling adventure and get to progress, but can only go so far in their levels. Members have an almost unlimited potential to become very wealthy and very powerful. They get to play mini-games that are not available to non-members, as well.
Each player has the ability to complete levels based on their own interests. For instance, someone wanting to gain levels (rs gold) in combat will need to fight others to gain more combat points. Whereas, someone interested in making items to sell may want to work on gaining more levels in something and mining. There seems to be virtually something for anyone interests at Runescape.