While living in the Big Brother house is fun for houseguests as they enjoy competing, relaxing, and getting to know other people, there are also hardships. Houseguests are away from their friends and family, cut off from all outside communication and activities. They deal with constant feelings of paranoia and the stress of trying not to get voted out.

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There are also rules that every Big Brother player must follow while in the game, such as not engaging in any physical violence, not bringing in phones or other communication devices, and never revealing to others what they talk about in their Diary Room sessions. Some rules, however, aren't as out in the open.

No Singing Or Movie Quotes Allowed

Azah Awasum on Big Brother 23 premiere

While houseguests can sing in the house, they cannot sing recognizable songs (that aren't in the public domain, like "Happy Birthday") or sing different words to the tune of a known song (Frankie got in trouble for doing this.) The same goes for reciting movie quotes. This is due to potential copyright issues, reports Mental Floss.

This explains why Azah from season 23 was constantly singing, but only made-up songs about what was going on in the house, in a non-recognizable tune. She found a basic melody to turn everything from cooking and cleaning into a more entertaining experience without violating any rules.

Certain Clothing Is Not Permitted

Tom Green from Celebrity Big Brother holding a cup of coffee and wearing a T-shirt with cassette tape images on the front.

While the Big Brother houseguests arrive with suitcases full of their belongings, including tons of clothing, there are some rules in terms of what they can and cannot bring. Most notably, houseguests can't wear any clothing with designer labels or logos to avoid branding issues.

But the restrictions go beyond that, according to The Richest. For example, houseguests can't wear silk material or patterns like polka dots or thin stripes, but the reason makes sense: the cameras don't pick up these materials or patterns well.

They Can Be Searched

A group of Big Brother houseguests laughing and smiling in a pool.

When houseguests arrive, as per their contract, they can only bring certain things with them, reports Reality Blurred. The contract also notes that they can be searched before entering the house to ensure that they are not bringing in items they shouldn't.

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Among these items houseguests can't bring into the house include their phones, or any device with an Internet connection. The reason is to ensure that they remain completely cut off from the outside world, which is a requirement of the show. That means they also can't bring alarm clocks or functioning watches so they never know what day or time it is.

They Have to Watch At Least One Season

Nicole and Hayden from Big Brother laughing together outside.

Some of the players who come into the Big Brother house are self-professed superfans who have watched every season of the show from the very beginning, dissecting every moment, strategy, and aspect of the show.

But it's no secret that many houseguests are cast on the show and weren't actually fans beforehand. Because producers want to ensure these people have at least an idea of what they are getting into, all houseguests who aren't already familiar with the show must watch at least one season before joining, reports Men's Health. The purpose is so they gain an understanding of the rules and develop a strategy of their own. If some players had done this, they might not have made some of the funniest mistakes on Big Brother.

They Have To Quit Their Jobs

Brian Hart's eviction from Big Brother walking out of the house with his bag as a live studio audience looks on.

While each houseguest is introduced in terms of where they live, how old they are, and what they do for a living, technically, they all need to be unemployed to join the show, according to RealityBlurred. Because there's no telling how far they will make it, each person has to commit to the entire 96-day filming schedule.

Depending on the job, some houseguests might be able to take a leave of absence from their position and thus don't have to outright quit. For others who work for themselves, they can figure things out. But no one can have any work-related obligations while playing. That could have led to an unfortunate situation for some of the worst Big Brother losers who didn't end up making it far in the game.

They Can't Talk About The Show After

Enzo from Big Brother wearing sunglasses and a hoodie.

If it seems like former players who come out of the woodwork years later to discuss parts of the game are just trying to get their 15 minutes of fame back in the spotlight, that might not necessarily be the case.

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According to Reality Blurred, part of the contractual obligations include not being allowed to speak about the show (outside of approved interviews) for at least three years. Should a houseguest violate this contract, they could end up having to pay a hefty fine.

Prize Money Can't Be Shared

Hannah sitting behind Derek X. hugging him on Big Brother.

While it would make sense that those in the finals might want to incentivize people they know will be on the jury to vote for them to win, like promising them a portion of the winnings, this understandably isn't allowed, according to Showbiz Cheatsheet.

The contract states the only one person can win the final prize money and cannot use it for bribes. How is this enforced? Since the houseguests are filmed 24/7, and aren't permitted to whisper, unless they happen to know one another prior to going into the house, there's no way to make such deals without production stepping in and shutting them down for a rule violation.

There's No Hiding

The Sea Glass bedroom from the 23rd season of Big Brother.

The most private conversations are held on the show with two people under covers in a bed, or in vacant rooms, whenever houseguests can find one. There's no place to hide to have a secret chat, and this is by design.

Not only is the furniture bolted to the ground so it can't be moved to allow people to hide behind, or even under, it, according to The Los Angeles Times, but even windows are two-way mirrors. The doors are also designed so they can't open too wide, and the wooden storage chests at the foot of each bed have dividers so people can't try to hide inside one to overhear a conversation. The smartest Big Brother players had to find ways around this rule and create their own spots for clandestine strategizing.

Pens And Paper Aren't Allowed

Johnny Mac and Becky from Big Brother sitting at the kitchen island, talking.

When houseguests are seen trying to take mental notes of clues that are presented throughout the house in preparation for a challenge, or figure out numbers for alliances or voting, they really do only have their memory to use. That is because among the many items not permitted in the house are pens and pieces of paper, reports Showbiz Cheatsheet.

Houseguests have found clever alternatives to keep "notes," like using food or even game pieces. This explains why so many conversations happen over the cheese board, with the pieces being used to explain strategy.

You Have To Speak English

Christmas from Big Brother holding her head

Not only do players have to ensure that speech is intelligible at all times, which means following the rule of keeping mic packs on 24/7, they also have to only speak English, according to TheTalko.com. (The language in question, of course, changes for other versions of the show to whatever the native tongue is in that country.) Without such a rule, fans would not have been able to fully appreciate some of the funniest Big Brother players.

If it so happens that two people in the house speak the same second language, they are not allowed to communicate with one another in that language. This allows for both production to be able to understand what is going on at all times and all houseguests to be on a level playing field in terms of how they can communicate with one another.

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