As one of the most prolific game series to ever be published, The Sims is a franchise that has spanned four official titles and dozens of expansion packs. The Sims is well known in the gaming world for its versatility, broad appeal, and endless replay value. In The Sims, you can live out your wildest fantasies, or make other suffer your worst nightmares. Considering that this title was the first true sandbox game, it's fair to say that The Sims paved the way for countless other open world and simulation titles.

The backstory behind the creation of The Sims is actually kind of interesting. After losing his home to the devastating Oakland Firestorm of 1991, Will Wright, the primary developer of The Sims, wanted to try and recreate his experience of rebuilding his homes and replacing his possessions in the medium of a game. Maxis was initially skeptical of this concept, and gave Wright very limited resources and funding at first. However, Wright's game was a smash success that launched a dynasty that has spanned close to two decades.

Here are fifteen super interesting facts about The Sims that you might not have heard of before.

15 The Gameplay Of The Sims Is Based On Real Psychological Theories

We all love The Sims for being such an endlessly fun and challenging game, but there's actual science to the gameplay of this series. One of the core elements used to help design your Sims wants and needs actually dates back to a research paper written in 1943 by Abraham Maslow.

Maslow was an American psychologist who is best known for his famous Hierarchy of Needs. This pyramid-shaped structure sorts human needs into five ranked categories, including Physiological, Safety, Love/Belonging, Esteem, and Self-Actualization. For example, if your Sim is throwing a tantrum because they have to pee, their Physiological needs are not being met. If your Sim tells an off-color joke that doesn't land, their Esteem might be damaged. Finally, if your Sim meets their Lifetime Aspiration, they reach a point of true Self-Actualization.

14 Sims Can "Age Up" At Any Time With The Birthday Cake

The Sims is especially known for its aging mechanic. Waiting for one particular Sim to "age up" can sometimes feel a little boring or frustrating for players who have a specific goal in mind for their tiny computer people. However, there's actually a super easy way for you to force age your Sim families.

All you actually have to do is go into the Buy menu and purchase a Birthday Cake item. Once you've placed the cake in your Sim's house, and select the Sim you want to age up in the "Throw a Birthday Party For..." interaction from the item. You technically don't need other Sims besides the Birthday Boy to be there for the party, but it's a little depressing otherwise. The one stipulation here is that you can't age Elder Sims to their deaths.

13 You Can Influence The Gender Of Your Sim's Babies

Part of the fun of The Sims is creating your own custom families and lineages that can last for (in-game) decades. Just like in the real world, crafting a perfect life for your Sims can sometimes be thrown off by a surprise baby or two. Pregnancy has been a part of the game since it's original release in 2000, but it wasn't until The Sims 3 that players were able to influence the gender of their Sim's babies.

Starting from The Sims 3, there's a cool trick you can use to change the biological gender of your Sim babies while they are still in vitro. If you want your Sim to give birth to a female baby, all you have to do is feed the mother three or more watermelons. If your Sim wants to have a boy, you need to feed her three or more apples.

12 There's A Secret Monster Hiding In The Game

Conspiracy theorists, rejoice! The Sims has something for everyone, including you, so keep your tin foil hats on. This is one of those video game urban legends that as a kid, absolutely nobody would believe when you told them. It's along the same lines as that old chestnut about some secret cheat code existing that would make Lara Croft appear topless. The only difference is that this particular rumor is true.

In the original Sims neighborhood, as well as in the Downtown and Vacation expansion packs, you have a very slim chance to see the Loch Ness Monster appear either in the lakes, or by the oceans of this game. The game's developers have since confirmed this rumor, and have established that the monster's name is actually Emily. If you don't want to wait around forever for this sea serpent to appear, just use the "nessie" cheat.

11 You Can Play With Your Own Music

One of the more memorable things about The Sims series has to be the music, especially the moving piano ballads from the Build and Buy menu in the first game. There's something very wholesome (and honestly, kind of voyeuristic?) about watching your Sims have the time of their life as they dance to one of the many in-game radio stations.

However, if you get a little sick and tired of listening to bangers like Feefa Foona Wabee, there's a way to listen to your own music while playing the game. Go into your install of The Sims and locate the Music folder. Here, you'll find another folder Stations, which contains all of the music your Sims can listen to through their stereos. Detailed instructions can be found here.

10 You Can Summon Santa Claus

If you're one of those people who is outright obsessed with the holiday season, The Sims has a cool surprise in store for you. Considering that The Sims doesn't exactly follow a calendar in the way that some season-based games, like Stardew Valley, does. That means that it's up to you to provide some holiday cheer to the tiny digital creatures you sometimes torture out of boredom.

A little-known fact about the original Sims game is that with the right combination of ingredients, you are able to summon Santa Claus. Here's how you get Jolly Old Saint Nick to make an appearance: set a plate of cookies next to a lit fireplace and a Christmas Tree. Make sure every member in your household is asleep, and then around 3:00 AM, Santa will appear and leave some presents.

9 Simlish Is Made From Several Languages

One of the most memorable things about The Sims absolutely has to be the weird, almost comprehensible language they speak, known as Simlish. The game's developers originally planned on having their Sims speak English, but they were worried that their Sim's repetitive phrases would start to sound a little cheesy and stale.

Will Wright, the primary developer of the series, was inspired by the Navajo Code Talkers of World War II, and decided to use the Navajo language, along with a mix of other languages, like English, Tagalog, and Ukrainian, to create The Sims' distinct verbal patterns. Simlish is not a real language, as it lacks grammar and syntax rules, but some dedicated fans have created a short vocabulary list that you can study in your free time.

8 The Sims Originally Had A Different Name

As one of the first and most prolific sandbox games, The Sims has been monumentally influential in the history and development of video games. Originally, the developers of this game envisioned The Sims as being a lot of different things, including an architectural design program.

The game's original working title was actually "Doll House," because Wright developed The Sims to reflect the experience of playing with an open-sided version of the popular children's toy. The name was panned by Maxis' marketing department, who thought that referencing a "girl's" toy would alienate the young males who made up the lion's share of the gaming market at the time. The Sims now takes its title from the "simulated" people you control in the game.

7 Pets Were Originally Supposed To Be In The First Game

One of the most fun and indulgent parts of The Sims has to be when you make yourself, your friends, and your family in the game. There's no better way to make fun of your friends than when their Sim-self is doing something goofy. However, for a long time, people's Sim families were incomplete because there was no way to add pets to the game.

Wright has previously mentioned that he originally planned on including cats and dogs with the first game, but programming animals was too difficult at the time to do reasonably well. This obviously changed in The Sims 2: Pets expansion pack, where dogs, cats, and horses were made available to add to your families. The Sims 2: Pets is also coincidentally the most popular expansion pack of all time in the series.

6 The Sims Are On A Postage Stamp In France

As time has progressed, the world outside of the nerd-sphere has begun to accept and recognize video games as important parts of our culture. Back in 2005, the French postal service, La Poste, decided that it wanted to honor some of the most prolific gaming series through a "Heros des Jeux-Video" collection of stamps. These stamps featured characters, such as Mario, Pac-Man, and Laura Croft, but they also happen to feature two characters from The Sims.

In 2005, the stamp was worth €0.33, which is about $0.40 USD. However, it's likely that the value of the stamp has increased over the past decade. The stamp features an image of a male and female Sim fighting over a large green PlumBob.

5 Two Uninvited Guests Can Make Or Break Your Sims' Parties

The Sims is known well for its cast of recurring playable. Characters, such as the Goth Family, the Crumplebottoms, and the LandGraabs have a special place in all of our hearts. The same can be said for the game's NPCs. One of the most prolific and well-loved NPCs has to be the Tragic Clown. It's known that the Tragic Clown will show up when your Sims are feeling at their lowest, but there's another secret place that he can pop up.

If your Sims ever throw a party that is an absolute disaster, place one of the giant cakes that come with the House Party expansion packs. Instead of a hot dancer, you might get a nasty surprise visit from the Tragic Clown. Alternatively, if your party is off the hook, Drew Carey (of all people) might actually turn up to get turnt.

4 Simoleons Are Based On A Real Currency

Everyone who has played The Sims is familiar with the in-game currency, known as Simoleons. Considering that The Sims was partially meant to be a criticism of consumer culture, it's no surprise that the start and end of all of your sim's aspirations come down to the all mighty dollar (or Simoleon, in this case.) However, the Simoleon is actually based on a real-world currency.

Simoleons get their name from a British sixpence coin. A popular slang term for a sixpence was a "simon," which the game's developers changed into simoleons. Another interesting fact is that the estimated value of a Simoleon is estimated to be approximately worth $1.6 USD, putting it at a higher value than both the Euro and the Pound.

3 There Was A Real Life The Sims House In The Netherlands

This one is for all you exhibitionists and voyeurs out there. In order to promote the release of The Sims 2, EA and Maxis decided to create a real-world Sims house that people could observe and interact with remotely. In 2004, they built a house with glass walls (even in the bathroom!) in the Netherlands.

A family of four was recruited to live inside the house for just under a week. The family was visited by strangers, who were able to see straight through the clear walls of the house. The family also received instructions from the internet to perform specific Sim-like actions and activities for all the world to see. The Netherlands was also the country of origin for the Big Brother series, so this venture into voyeurism isn't too out of left field.

2 The Sims Was The First Game On The Cover Of Newsweek

While this particular magazine has stagnated with the rise of the internet, much like all print media, back in the early 2000s, Newsweek was still an important journal that covered international politics, media, and technology. Since 1933, this magazine has been in and out of print, and currently exists in both a paper and digital format.

The article, published in November of 2002, mostly focused on MMORPGs, as The Sims: Online was originally expected to be a smash hit. Gamers were even expected to pay $9.99 a month in order to access the servers for the game. Despite the fact that this particular title was never quite as popular as EA and Maxis might have hoped, Newsweek's cover was still monumentally important because it was an acknowledgment that video games are a legitimate media industry.

1 The Sims Is The Best-Selling Game Of All Time

One of the most incredible facts about The Sims franchise is that it is one of the best selling video game enterprises of all time. It's incredible to think that this somewhat simple game has made such a monumental profit over the past two decades.

As of 2017, The Sims has sold over 200 million copies worldwide. When comparing sheer volume of games sold, this means that The Sims has beaten the Final Fantasy series, Minecraft, and FIFA in pure numbers. The Sims franchise has even sold more copies than the Assassin's Creed and LEGO game franchises combined.

You can definitely look forward to more Sims games in the future, as the next installment of the series, The Sims 5, is rumored to be arriving in late 2019.