The Championships, Wimbledon has the strictest dress code of all the major Grand Slam tennis tournaments.

The players must wear white. All white. It's tradition.

The All-England Club, where the tournament is played, takes this rule very seriously.

The dress code dates back to the 1800s, when tennis was played at social gatherings. The sight of sweat spots through colored clothing was thought unseemly, especially for women, and "tennis whites" became an institution. 

Wimbledon has carried on this strong tradition, even after the US Open allowed colored clothing in 1972.

And the dress code has only gotten more strict in recent years. Last year, the Club issued 10-part "decree" included in the competitor's guide all players must follow. Included in the decree are new rules revolving around the wearing of white, including stipulations like:

• "White does not include off-white or cream."
• There can only be “a single trim of color no wider than one centimeter.”
• "Any [colored] undergarments that either are or can be visible during play (including due to perspiration)” are not allowed. 

In 2013's tournament, seven-time Wimbledon champ Roger Federer was told his orange-soled shoes were too much and he would need to switch them for the next match. "My personal opinion: I think it’s too strict," Federer said in a press conference. 

Players have also claimed Wimbledon's argument of upholding tradition doesn't hold water. In 2014, Martina Navratilova — who has won the tournament nine times — was told the blue stripes on her skirt crossed the line. She questioned how that was possible, since she's worn the same type of outfits at Wimbledon throughout her long and storied career. Some of the pieces are even held by the Wimbledon Museum.

“I think they’ve gone too far,” she told The New York Times.

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Russian photographers Vadim Mahora and Vitali Raskalovym have gained a lot of media attention after they published their illegal photographs of the Great Pyramid of Giza.

For years, the two photographers have risked frightening heights and legal implications to scale some of the world’s highest and most well-known buildings which they highlight on their website, On the Roofs.

The images are breathtaking and capture views of these famous destinations we might not otherwise see, but their work does come with controversy. This is why they urge that others don’t follow in their path. 

From climbing to the top of China’s highest skyscraper to capturing images of Barcelona’s Sagrada Família from above, here are some of their most stunning and risky shots. 

The Russian photographers have recently gained attention for capturing these illegal photographs of the Great Pyramid of Giza in Cairo, Egypt.

Learn more about the Giza pyramids.

To get the shot, the two hid from guards for four hours after closing time before climbing the pyramid, which they say can come with a punishment of one to three years in jail when caught.

But the two have been climbing roofs for years across destinations like Cologne, Germany, where they were able to capture a bird’s eye view of the Cologne Cathedral, the seat of the Archbishop of Cologne and a UNESCO World Heritage Site.

Learn more about the Cologne Cathedral.

John Malone just added a new trophy to his massive property collection.

As reported by The Wall Street Journal, the chairman of Liberty Media Corp. paid $38 million for a mansion on Jupiter Island.

The former home of Horst Brandstätter — the founder of Playmobil — this beachfront estate has it all.

Originally listed at $45 million, the sale was brokered by Ken and Kandyce Meierling of Engel & Völkers.

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Built in 1997, this 22,057-square-foot home sits on over nine acres of land with Atlantic and Intracoastal views.

The property stretches 506 feet along the ocean and 510 feet along the Intracoastal. That kind of location affords some pretty fantastic seascapes.

The estate shelters an 8,400-square-foot main house with three bedrooms, a guest house, and a 3,000-square-foot beach house with two bedrooms, an office, and a kitchen.

Licensed psychotherapist and relationship expert Rachel Sussman explains how often is "normal" for couples in happy relationships to have sex. Turns out there's no specific answer. 

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The New York City subway system has been around for over 110 years.

Luckily, Google has an awesome collection of images taken from the New York Transit Museum that shows off what the old subway trains looked like, beautifully highlighting what riding the subway was like back in 1904.

From wood-paneled exteriors with ceiling fans to advertisements from the early 1900s, we've collected our favorite photos so you can travel back in time.

Note: Google Virtual Tour provided by Black Paw Photo.

The journey begins at the subway's turnstiles, which were wooden back then.

The New York Transit Museum was actually created in a decommissioned underground station in Brooklyn.

Vintage signs from the time period are on the walls.

It has been a few weeks, and I've been waiting for someone to touch on what is truly awful about the "Entourage" movie.

But no one has come forward.

So I guess it will have to be me.

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Nothing quite says "I've made it" like a luxury yacht decked out with amenities. 

The superyacht has become a status symbol among the wealthiest in tech — from Google CEO Larry Page's 193-foot "Senses" all the way up to Microsoft cofounder Paul Allen's 414-foot "Octopus." 

But even if you're a billionaire fresh off of an IPO, there are a lot of things to consider before choosing to add a yacht to your toy collection. 

"Buying a yacht — it’s not a logical business decision. You can’t rationalize it," Rupert Connor, owner of crew agency Luxury Yacht Group, said to Business Insider. "You can’t use a spreadsheet to say, 'This is the breakeven point for happiness.'"

How much are you willing to pay? 

You can usually find listings for boats currently available for purchase or charter on yachting industry sites like Yachtworld.com and Yatco.com. Individual firms, like Fraser Yachts, often maintain their own internal listings. 

The most inexpensive yacht currently listed for sale on Fraser Yachts' web site is a 60-foot boat called "Reel Action." It's listed for $239,000. 

On the higher end of the scale, there's "Imagine," a 213-foot yacht that's on the market for $82 million. 

But that list price doesn't even begin to tell the whole story of how much money you should be willing to spend if you decide to buy a yacht. 

Annual operating costs — fuel, crew salaries, maintenance, and paint, for example — can be very steep.

Though many in the yachting world have said that you should expect to pay 10% of the purchase price on operations each year, Connor says that fees can actually be much higher than that.  

Connor stressed the importance of surveying a yacht before buying it, as you may uncover structural flaws whose fixes will definitely stretch your budget. 

"As boats get older, the capital value goes up, and the operating and maintenance costs also go up," Connor said. "The 10% figure is wrong, and it gets repeated all the time." 

For a 200-foot-yacht, like Page's "Senses," fuel alone could cost about $800,000 annually. Maintenance might cost as much as $750,000 a year. 

Page reportedly paid $45 million for the yacht in 2011 — it has a jacuzzi, helicopter pad, and interiors designed by Philippe Starck. 

How often can you reasonably use it? 

Some would-be yacht owners might think they could offset the costs of a yacht by making it available for charter when they're not using it. 

However, Connor says that it does not make much financial sense to buy a yacht just to charter it, as the operating costs will far outweigh any profit you might make. 

"Most people who buy yachts don’t have to rationalize the purchase, though. They can afford it," Connor said.

Michael Busacca, U.S. Commercial Director and COO at Fraser Yachts, says it is possible to make money out of chartering your yacht if you give up the freedom of using it whenever you want.

Still, it's probably best not to depend on charter to make up the difference.  

"The owner needs to be very flexible on their own personal usage while in charter, especially during peak charter periods such as Christmas and New Years," Busacca said to Business Insider. 

How many crew members are you looking to hire? 

The number of crew members you'll hire will vary depending on the size of the yacht. While an 80-foot yacht might require only two crew members to operate, you might need to hire up to 60 people if you have a larger boat. 

According to Fraser Yachts, some of the most commonly hired crew members include a captain, chief mate, chief engineer, chief steward, chef, and deckhands. 

Luxury Yacht Group suggests setting a salary of $7,000 to $15,000 a month for an experienced captain. Mates should make between $3,000 and $7,000 a month, while a deckhand makes between $2,000 and $4,000. Crew members should be paid more on larger yachts, according to Luxury Yacht Group's guidelines. 

Allen reportedly keeps a permanent crew of 60 onboard "Octopus." The yacht has 28 cabins just for the crew, according to the Superyacht Times.

What amenities do you want?

Yachts can come with all kinds of special features. 

"Of course, new build yachts can be fully customized to the client's liking," Busacca said. "Many requests include, but are not limited to, on-deck hot tubs, gym, wave runners, tenders, separate crew quarters, on deck master stateroom, satellite communication and entertainment systems."

Google chairman Eric Schmidt reportedly paid $72.3 million for the 194-foot yacht "Oasis" in 2009. The superyacht has plenty of amenities, including a pool, jet skis, and a gym that can be converted into a disco. 

Allen's "Octopus" yacht is fully equipped with a pool, two helicopters, a movie theater, basketball court, and a recording studio.

Former Oracle CEO Larry Ellison named his 288-foot yacht "Musashi" after a revered 16th-century Japanese warrior. The boat's amenities include two master suites and a basketball hoop.

Mark Cuban's 288-foot "Fountainhead" yacht is the sister ship to Ellison's "Musashi." The two ships look nearly the same from the outside, though Cuban reportedly went for a more antique-inspired interior.

Where will you register the yacht? 

Where you decide to register your yacht is very important, as it determines how much you will pay in taxes, how liable you will be for operating in international waters, and how you can operate the yacht as a commercial enterprise. 

Places like the Cayman Islands and Marshall Islands are popular among yacht owners because they operate under tax laws similar to Delaware's, where many businesses often choose to incorporate. 

Page, Schmidt, Allen, Ellison, and Cuban all registered their superyachts in the Cayman Islands, according to MarineTraffic. 

"There are tax benefits to registering in the Cayman Islands," Connor said. "The flag behind the yacht shows which rules you're following."

Clive McCartney, U.S. Manager of Yacht Services at Fraser Yachts, explains what you should take into consideration.

"There are many things to consider including tax implications, operational requirements and the service required from your flag state," McCartney said. "Do they have their own surveyors or do they contract it to third parties, what safety code do they apply, how do they treat exemption requests, and what is their safety record? Registration of the yacht should be discussed with your Maritime Attorney and your Yacht Manager before making a decision."

Malta and the Isle of Man are also common registration points among European yacht owners. 

SEE ALSO: How to buy a private island — even if you're not a tech billionaire

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It's become clear that Aby Rosen does not like Wall Street.

The first clue was his disdain for a beloved Picasso wall hanging inside The Four Seasons Restaurant.

The second was his fierce disdain for The Four Seasons Restaurant in its entirety — which he is kicking out of his midtown Manhattan building.

The third clue, his decision to close down Brasserie, the restaurant below The Four Seasons, made his dislike for Wall Street obvious.

Fine, then.

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We've come a long way since the days of "I Love Lucy" when the idea of sex on TV was so taboo that even married couples were shown sleeping in separate beds.

Since then, our ideas about sex have opened up a lot — we've become far more accepting of everything from sex before marriage to sex between same-sex couples, and those trends have picked up pace since the 1970s.

But in a few areas, like sex outside of marriage, we've actually grown a tad less accepting.

At least that's according to a recent study in the Archives of Sexual Behavior which looked at data from a huge sample of Americans included in the General Social Survey (GSS).

Here are its biggest findings:

We've grown more accepting of sex before marriage

In the early 70s, just 29% of Americans (35% of men and 23% of women) thought it was okay to have sex before your wedding day. To be more exact, when given options on a scale of 1-4, with 1 being "always wrong," and 4 being "not wrong at all," less than a third of people would choose "not wrong at all."

About a decade later, this percentage grew to around 42%, where it stayed through the 90s. In the 2000s, it rose to nearly half (49%), and in the 2010s it hit 55% (59% of men and 52% of women).

We've grown more accepting of gay and lesbian sex

Acceptance of sex between gays and lesbians has tripled since the 70s, with the most growth happening amongst young people. Just over 1 in every 5 young people who were between 18 and 29 in the 1970s said sex between people of the same gender was "not wrong at all." By the 90s, this percentage rose to 26%. By the 2010s, more than half of Millennials (56%) approve of sex between same-sex partners.

and...

We're reporting having more sexual partners

In the 1980s, people said they had an average of 7 sex partners since age 18 (roughly 11 for men and 4 for women). In the 2010s that number rose to 11 (roughly 18 for men and 6 for women).

We're reporting having more casual sex

Just about 35% of 18-29 year olds in the late 1980s said they had sex with a casual date (44% of men and 19% of women). Yet nearly half (45%) of Millennials in the 2010s (55% of men and 31% of women) said they'd had sex with a casual date.

These increases don't necessarily mean we're simply having more casual sex or sex partners, and could also be a result of people being more comfortable about admitting they've had more casual sex or sex partners in the first place.

but...

We've grown less accepting of sex outside of marriage

Although levels of acceptance regarding sex between two people who are married to other people has stayed relatively low throughout the years, acceptance rates have declined pretty significantly since the 1970s.

About 4% of adults said sex between two people who were married to other people was "not wrong at all" in 1973 (6% for men and 2% for women), compared to just 1% of people in 2012 (2% for men and less than 1% for women).

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No one wants to be that offensive, insensitive tourist.

While you may not do it intentionally — or even realizing you're doing it — certain kinds of behavior that Americans wouldn't think twice about aren't as accepted or favored in other countries around the world.

We spoke to Robert Hickey, the deputy director of the Protocol School of Washington, and author of "Honor and Respect: The Official Guide to Names, Titles, and Forms of Address," to find out what some of these faux pas are.

Take a look below so you know what to avoid next time you're in a foreign country.

1. Don't assume that it's ok to address someone informally.

Hickey points out that most other countries are more formal than the US when it comes to addressing people.

For Americans, Hickey says, "intimacy equals respect." Whereas in most other countries, "formality equals respect."

So while calling someone you hardly know by their first name in America is a sign that you have a good relationship with them, in other countries calling them by Mr. or Mrs. is seen as a sign of respect, which in turn signifies a good relationship with that person.

"The Koreans work with someone for 20 years and they call them 'Mr. last name,'" Hickey said. "It doesn't mean they're not great friends, it just means they show one another that respect. In our culture that's distance."

2. Don't dress to impress.

According to Hickey, originality and individuality is valued much more in the US than it is in most other countries. Americans constantly strive to differentiate themselves — often with what they choose to wear — while in many other countries, such as those in Asia, it's not good to stand out.

"For us, getting dressed is a creative moment in our day because we're all struggling to be unique and different," Hickey said. "Most of these cultures don't value originality all that much. So in some ways, when you go there, dressing a little more in a boring way with less personality is seen to be respectful."

3. Don't assume all foreigners want to be like us.

Hickey says that while people from other countries around the world are often curious about Americans — mostly because of the prevalence of American media — they don't necessarily want to be an American or live in the US.

"They don't want to be like us," Hickey said. "They want to be citizens of the world, just like we're citizens of the world. They want to be comfortable anywhere. But they don't want to be like us because they see the holes in what we have."

4. Slow down while introducing yourself.

In all of his classes, Hickey does an exercise where participants sit in a circle and throw a ball around. Whomever receives the ball has to state their name, but they have to pause in between their first and last names. Hickey says this is because names are important, and we have a tendency to speed through our names, which can confuse foreigners, especially since this may be the first time they're hearing that name.

"When you're dealing with internationals, slow down," Hickey said. He also recommends expressing interest in someone else's name by asking them about it, since people love to talk about their names, and there's often a story behind it. "You learn so much. Names are really cultural."

5. Don't only talk about the US in conversations.

When someone is talking about how things are done in their country, it's easy to reply with how things are done in your country. But Hickey says the conversation won't go anywhere this way, and that it's better to express interest in another country by asking follow up questions.

"It's not playing tennis; tennis is not a conversation," Hickey said. "A conversation is getting to know somebody. If you say, 'we do it this way in Chicago,' the other person can ask, 'has it always been that way, do you think that's the way your parents did it or has it changed in the last 30 years?' Then it becomes a conversation."

SEE ALSO: How NOT to behave in 15 countries around the world

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Actor Jeff Goldlum was recently named to GQ’s list of the 20 Most Stylish Men Alive.

In an interview with the magazine about his personal style, the newly married actor was asked how he responds when a woman asks what you think of her outfit.

Here's his advice for men everywhere:

“The traditional wisdom is of course to be positive. Because, even though I embrace truthfulness—I'd say I am a truth seeker, and truth teller, and person who's devoted his life to authenticity (under imaginary circumstances and in real life, frankly; it's an ideal toward which I aspire, and I'm a humble student of it)—I also feel that in human relations (when not under imaginary circumstances, especially), the way to skin the cat—and the way toward integrity, in fact—is not necessarily always to tell the whole truth and nothing but the truth. If they really ask, and you have some kind of opinion that you think can be constructive, maybe then. But err on the side of restraint. Restraaaaaint. And say ‘Mm-mm-mm. Well, you look good in everything! Da-da da-da da-da. Et cetera et cetera.’”

You got that? "err on the side of restraint" and when in doubt, "You look good in everything!"

Read Goldblum's full interview with GQ here.

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