The basic gameplay aesthetic of The Sims is well known to everyone, whether they play games on a regular basis or not: take control of a person or a group of people and guide them through life. While it's incredibly simple on paper, the details are what will catch you. Things like maintaining happiness, finding success, and forming relationships all fall within this vein of life simulation, but in the end, you can do whatever you want. That is the true appeal of The Sims, and the reason why it is so accessible to people of any age or gender. The most appealing nature of the game is the fact that it is a sandbox, which exposes more and more people to games without limits or goals. When you've spent time doing whatever you want, why go back to the linear model?

The entry point of The Sims 3, and the part of the game that players will spend the most time in, is the sim creator. The features of the creator have been rounded out and changed so that anybody can tweak things how they like with ease. While the body and facial structure settings have not really changed since The Sims 2, the clothing aspect has expanded immensely. While you can chose from a bunch of clothing as expected, you can also modify the clothing on the fly and then save your settings to share with other players. This includes colors, patterns, and texture. This sets the tone for the rest of the game, and shows the lessons learned from Spore. Rather than having customization tools be accessible to only a select few, everybody can now tweak things how they like.

The traits and personality aspects of creating your sim have also undergone a massive overhaul. As before, you pick traits and tweak the personality of your sim. However, instead of having a pool of points that go into certain attributes, you choose the traits of your sim at creation or as they grow up. These traits include things such as Evil, Couch Potato, Ambitious, Brave, or Artistic, among many others. These traits are often paired with an opposing trait. For example, your sim can not be Evil and Good-Natured at the same time. This drastically simplifies the creation process, and is a much-needed change from the previous system. You also choose your sim's favorites upon creation, which he or she will naturally lean towards throughout their life. For example, if they like classical music, when they turn on the stereo it will always be to classical.

The actual gameplay portion of The Sims 3 is virtually unchanged. The wishes system from The Sims 2 makes a return, although there have been some minor changes. For example, you spend your lifetime happiness to purchase rewards, much like before, but rewards also include new traits for your sim, such as Iron Bladder (almost never has to go to the bathroom) or discount diner (free food at restaurants). There is also the standard item rewards, but they are exceedingly expensive and hard to obtain. Your happiness meter now also has a cap, and if your mood exceeds that cap, the happiness points are fed directly into your lifetime happiness. There is also an opportunities system in place, where your sim can perform certain tasks for job, skills, or just because in order to earn some money or raise their standing in the world.

The mood system has been simplified as well. Gone are the needs of Comfort and Environment, and the old needs have been tweaked for more consistent and enjoyable gameplay. However, there is a new system of "moodlets" that increase or decrease your sim's mood. Comfort and environment fall into this, with comfort providing a mood boost and environment contributing positively or negatively, depending on the cleanliness of the area. You can also have moodlets from the current needs, such as sleeping long enough to acquire the Well-Rested moodlet or eating a particularly delicious meal to get Yummy. Finally, moodlets can come from other sources besides, such as achieving your lifetime wish, making a new friend, or buying new things for your sim. It's a much more streamlined system that allows players more freedom from the need to micromanage every need.

The skills system has been expanded upon in new and more interesting ways. For example, creativity has now been divided into three categories: writing, music, and painting. You can excel as a writer but be a terrible artist, or make loads of music busking but never sell any novels. There are also mini-achievements for skills, such as repairing ten plumbing items or earning a total of 30,000 in book royalties. These mini-achievements, along with being displayed on your sim's skills page, also give them direct bonuses, such as allowing them to sell their works for more or cook better meals.

Purchasing and building functions exactly as it did in previous games. There is no change whatsoever in that respect. Several elements of previous games and expansions, such as owning a car and the Family Inventory, make a return. However, you can now place items at a diagonal, which was sorely needed, and you can also tweak the colors, textures, and patterns of everything from couches to wallpaper. As with clothing before, you can save these patterns and then share them out with the world if you so wish.