The first game in The Sims series was released back in 2000 and was created by SimCity developer, Will Wright. The idea was to see and control what was going on in all those houses from the SimCity games. EA didn't put a lot of faith in the new series but it proved to be a huge success selling 16 million units. Since that time the series has turned out to be more popular that the SimCity series and has spawned many sequels which work at constantly fine-tuning and enhancing the series.
The premise to the series is the creation of a virtual avatar, called your Sim. Once created it is up to the player to create and maintain their home and every aspect of their life, with the most important ones being eating and sleeping. Your Sim will work, play and more based on the environment around them. You can always override their behavior when you think they might be doing something that you don't feel is beneficial. Meet their personal needs and your Sim will thrive and grow, let them down with an inadequate environment or poor choices in behavior and you risk permanent damage to your Sim.