The game has the same concept as its predecessor: players control their Sims in various activities and form relationships in a manner similar to real life. The Sims 2, like its predecessor, does not have a defined final goal; gameplay is open-ended. Sims have life goals, wants and fears, the fulfillment of which can produce both positive or negative outcomes. All Sims age, and can live to 90 sim days depending on the degree to which their aspirations are fulfilled. The Sims 2 builds on its predecessor by allowing Sims to age through six stages of life and incorporating a 3D graphics engine. Although gameplay is not linear, storylines exist in the game's pre-built neighborhoods.