• Writing a LinkedIn recommendation comes with a certain amount of pressure.
• Your coworker may be relying on you to help them get a new job, and because LinkedIn recommendations are public, what you write reflects back on you, too.
• Business Insider asked experts to provide some tips and samples help get the job done.

At some point in your career, a coworker may ask you to write them a LinkedIn recommendation. And believe it or not, the stakes for such a request can be pretty high.

Unlike traditional letter or phone recommendations, LinkedIn recommendations are public. That means anyone who goes on your profile can see what you wrote about your boss, coworker, employee, or client.

What's more, the person you're giving the recommendation to is relying on you to give a powerful statement on their qualifications — one that may or may not help them land their dream job.

And if you nail it, the recommendation you write could even end up helping you in the long run. "If you write a great recommendation, great recommendations are gonna come back to you," LinkedIn consultant Loribeth Pierson told Business Insider.

No pressure, though.

Luckily, career experts shared with us tips and samples for writing a stellar recommendation on LinkedIn. 

SEE ALSO: LinkedIn’s Career Expert reveals 3 ways to make your profile stand out

DON'T MISS: Here's what an effective LinkedIn profile looks like in 2018

SEE ALSO: I've read hundreds of LinkedIn messages while managing Business Insider's social accounts, and people often make the 7 same mistakes

If you can't give them a rousing recommendation or haven't worked with them in a while, turn them down

"Recommendations should be authentic and truthful," Vicki Salemi, career expert for Monster, told Business Insider. "Your name is on it. You don't want to endorse people who could be a poor performer."

If you're comfortable taking a direct approach, you could respond to a request with the following:

"Hello, X. I hope all is well. As you know, there were performance issues while you were an employee here. I don't think I'm the best person to be your advocate. Thank you for reaching out, and best of luck during your job search."

Or, to simply side-step the request without mentioning rough patches from the past: 

"I'm sorry, but I don't have the time right now. I think you should ask someone who can put the attention to this that it deserves."

If you're okay with recommending them, ask for what they'd like you to include

Your former employee, coworker, or boss probably has an idea for what they want to see in the recommendation.

If you didn't speak to them directly, you should send them a note like this to make sure your testimonial fits their needs:

"Hi, X. I would be happy to write you a LinkedIn recommendation. Is there anything in particular you want me to include? I want to make sure I'm writing the best recommendation for your LinkedIn profile."

Begin your recommendation by explaining your relationship

Defining how you two worked together gives the context that the reader will need to understand the rest of your recommendation. 

Begin by explaining how you know the person:

"Anna was my boss for three years at Software Corp., where her leadership, communication, and creative ideas always motivated our team."

"I was lucky to be one of Jordan's clients when he was a salesperson at Cute Pants, Inc."

The Insider Picks team writes about stuff we think you'll like. Business Insider has affiliate partnerships, so we get a share of the revenue from your purchase.

As one of the largest sportswear brands, Adidas is deeply rooted in the worlds of athletics and lifestyle.

For footwear and apparel alike, its new designs are state-of-the-art, and many of its past designs are considered fashion staples.

You might think that certain high-performance and classic sneakers never hit the clearance section, but Adidas' sales are often packed with great sneakers at amazing prices — and they just added a bunch of new styles.

Right now, you can save up to 50% on styles for men, women, and kids. Whether you're looking for a modern lifestyle sneaker like Prophere, a soccer-meets-boot hybrid like the A 16+ Pure Control Ultra Boost, or a brand classic like the Superstar, we suggest picking up a pair before your size runs out.

Also, don't limit yourself to just footwear — the sale goes for apparel, too.

Shop men's clearance styles at Adidas here.

Shop women's clearance styles at Adidas here.

Check out some of the best sneakers on sale below:

Men's Prophere

Adidas Prophere, $84 (Originally $120) [You save $36]

Men's A 16+ Pure Control Ultra Boost

Adidas A 16+ Pure Control Ultra Boost, $140 (Originally $200) [You save $60]

Men's Climacool 02/17

Adidas Climacool 02/17, $70 (Originally $100) [You save $30]

The National Science Foundation conducts a survey every two to three years to evaluate how good Americans are at science. The questions vary slightly from year to year, but they all have to do with basic facts in physical and biological sciences.

Both the general public and people who have obtained bachelor's degrees were stumped by the quiz. College graduates consistently scored higher than the general public, but didn't earn a perfect score on any question.

See if you can pass the most recent form of the test from 2016.

1. True or false? The center of the Earth is very hot.

Of the general public, 85% got this right, as did 89% of college grads surveyed.

Answer: True.

The temperature of Earth's core is an estimated 10,800 degrees Fahrenheit— as hot as the surface of the sun.

2. True or false? The continents have been moving their location for millions of years and will continue to move.

Of all those surveyed, 81% answered correctly, and 87% of college graduates specifically.

LG announced the G7 "ThinQ" smartphone on Wednesday, and it looks to be a solid, well-rounded, high-end device based on the brief amount of hands-on time I got to spend with it ahead of its unveiling. 

Will it make you rush out to upgrade from last year's smartphones, or even two-year-old smartphones? Probably not, but that's ok. Pretty much every recent smartphone release, including Apple's iPhones and Samsung's Galaxy S9, haven't really offered major reasons to upgrade every one or two years.

It's way too early to make a final conclusion on the LG G7, as I have yet to fully test its performance, camera, and feature set (a full review will be coming soon). But for now, check out the LG G7's design, what it offers, and what features it has that you don't get on other smartphones:

SEE ALSO: Everything we know about the OnePlus 6, one of the most anticipated smartphones of 2018

Here it is, folks: The LG G7.

In many respects, the LG G7 isn't that much different than most other high-end Android devices of late. You get:

- A 6.1-inch quad-HD display.

- A nice design with slim bezels.

- A fingerprint sensor.

- Water resistance. 

- The latest Snapdragon 845 processor from mobile chip maker Qualcomm.

- 4GB of RAM.

- 64GB of storage.

- A 16-megapixel dual-lens rear camera. 

- An 8-megapixel selfie camera. 

- An incredibly loud speaker, but it's not in stereo. 

- A 3,000mAh battery. 

- Wireless charging and fast charging. 

- Android 8.0

- A headphone jack (some Android phones have it, like the Galaxy S9. Others, like the Google Pixel 2, don't). 

What the LG G7 offers that you won't find on most high-end Android devices.

If you choose the LG G7, you'll get these specific features that you won't usually find on other high-end Android smartphones: 

- An audio DAC for higher quality music through headphones than most other smartphones. 

- A camera that uses LG's "ThinQ" AI, which recognizes objects you want to shoot and automatically adjusts the camera settings for the best photo. 

- A rear camera lens that acts as an ultra-wide lens that spans 170-degrees. The regular wide lens spans 71-degrees, which is in-line with most other smartphone cameras. Most other smartphones with dual-lens cameras also use their second lens for different features, like enhanced zooming.

LG's "ThinQ" AI camera worked pretty well, and I'm excited to test it further.

LG's "ThinQ" AI will adjust the camera settings depending on what object or setting you're shooting, and it seemed to work pretty well during the demo event I attended. I got reassuring words that floated on the screen telling me how the phone was correctly interpreting the object I was shooting. 

For the plant I was aiming at with the camera, the LG G7's "ThinQ" was telling me "leaf,""green," and "close-up," which is all pretty accurate. I can't show you the photo it took, but it looks pretty good from my short test. I'll be testing the ThinQ AI more with different scenarios when I get my hands on a review unit. 

"Star Wars" characters and the actors who play them are icons. So it's hard to imagine anyone else in the role.

But other big name actors put their names into the audition pool. If anyone else had been cast, these movies could have been completely different. 

Here are 15 actors who were almost in the "Star Wars" movies. 

Al Pacino turned down the chance to play Han Solo.

During the "An Evening with Pacino" event in 2013, the actor revealed that he could have played the iconic role of Han Solo in the "Star Wars" franchise.

"It was mine for the taking but I didn't understand the script," he said.

Burt Reynolds regrets turning down the role of Han Solo.

Burt Reynolds told Business Insider that he wasn't interested in that sort of role at the time he was asked.

"I just didn't want to play that kind of role at the time," he told BI. "Now I regret it. I wish I would have done it."

Sylvester Stallone auditioned for the role of Han Solo.

Sylvester Stallone told Jimmy Fallon on NBC's "The Tonight Show" that he bombed his "Star Wars" audition on purpose.

"Let me just make it easy for you," Stallone told Fallon of what he said to George Lucas and his producers. "I would look like crap in spandex leotards and a ray gun. Guys in space don't have this face. I get it."

We know our government as one of checks and balances, always ensuring that one branch has oversight over another. But in case of some kind of national emergency, the President of the United States has the ability to essentially turn the democratically-elected government into a sort of constitutional dictatorship, with him (or her) at its center.

This doesn't mean the chief executive has to enact all the powers at once or that, in an emergency, that they have to enact them at all. These are just the possibilities. In case you read this and think to yourself, "Holy cow, no one is ever going to really do that!" Guess again. Most of these have been done before.

There are four aspects to an emergency: the sudden onset and how long it will last, how dangerous or destructive it is, who it may be dangerous to, and who is best suited to respond. The President has to declare a state of emergency and indicate which powers he's activating.

SEE ALSO: The 15 countries with the highest military budgets in 2017

1. Regulate all commerce and business transactions.

Under the Trading with the Enemy Act of 1917, the President is allowed to regulate all the finances of the United States, including all international transactions.

2. Seize all privately-held gold stores.

Under the same 1917 act of Congress, the President has the authority to take all privately-owned gold coin, gold bullion, and gold certificates. The last time this was used was in 1933 to mitigate the effects of the Great Depression. Citizens were allowed to keep only $100 worth of gold.

Citizens were paid its value per ounce and for the cost of transportation as they were required to surrender the gold to a Federal Reserve Bank within three days of the order.

3. Take control of all media in the U.S.

Under the Communications Act of 1934, the President can establish the Office of Telecommunications Management, which oversees all media and telecommunications, regardless of advances in technology.

President Kennedy did this through Executive Order 10995 in 1962.

• Millennials sleep more than any other generation.  
• But even though they are getting on average 25 more minutes of sleep than most others, the quality of their sleep is suffering.
• Habits like staying up late, using electronics, and drinking before bed all can wreak havoc on your sleep cycle.    
• INSIDER spoke with several sleep experts to find out what habits are most harmful to getting a good night's sleep.

Millennials, on average, sleep more than any generation before them, according to Forbes. So if you fall into this category, you're likely getting the recommended seven to nine hours of sleep each night.

But if you're sleeping this much and still feeling tired throughout your day, a deeper issue may exist and your bedtime routine could be the cause.

INSIDER spoke with several sleep experts to find out which habits could be hurting your sleep cycle.

1. You're trying to fall asleep to Netflix.

A habit that may be keeping you from sleeping well at night isthe use of phones, laptops, or tablets before falling asleep. But unfortunately, this is messing up your circadian rhythm, which is your internal clock that helps regulate your sleep cycle, according to physician Dr. Saurabh Sethi, MD, MPH.

When staring at your phone or other electronics in the dark, your pupils dilate which allows more harsh light in. This, in turn, inhibits the production of melatonin, which is a natural hormone vital for falling and staying asleep, Dr. Sethi told INSIDER.

A good rule of thumb is to power down andput gadgets away about 30 minutes before going to sleep, according to Restonic.

2. You don't a have a bedtime routine.

Your body likes having a consistent bedtime, according to Dr. Sethi. The reason being that your circadian rhythm requires and enjoys that steady routine.

"Constantly changing your circadian rhythms decreases the amount and quality of sleep we get each night. You can improve your sleep hygiene by establishing a consistent schedule," Dr. Sethi said.

Try to go to bed only when you're tired, Dr. Karen Joubert, PT, DPT, the owner of Joubert Physical Therapy of Beverly Hills recommended, but aim for the same time every night and wake up at the same time every morning.

3. Distractions near your bed can keep you from sleeping well.

You may be surprised to discover that the room you sleep in can actually prevent you from having a good night's sleep, according to Dr. Sethi.

"It's wise to get rid of the clutter around your bed. Keeping your bedroom clear of distractions will help you clear your mind at the end of a long day," he told INSIDER.

Apple made a ton of money last quarter. Not that it was ever really in doubt.

The iPhone giant reported second-quarter earnings on Tuesday, posting $61 billion in revenue, partly powered by sales of 52.2 million iPhones.

The company also said that it was going to spend a record $100 billion buying back its own stock, and raised its dividends.

But beyond the big money numbers, Apple executives always like to tuck a few new details into its earnings report and conference call.

Some of the revealing nuggets may even hint at what Apple's next big thing. 

Here's what you may have missed in Apple's earnings report: 

SEE ALSO: Apple pops after beating Wall Street expectations — and it plans to buy back $100 billion in stock

Apple's "wearables" business -- which encompasses headphones and the Apple Watch -- makes more money than Ebay or Netflix.

Although Apple doesn't reveal Apple Watch sales, CEO Tim Cook has a penchant for describing the size of the business by comparing it to other, standalone corporations. 

As of Tuesday, "wearables revenue" over the past four quarters is "the size of a Fortune 300 company," Cook said. 

Apple defines "wearables" as Apple Watch, plus AirPods, plus its Beats headphone subsidiary. 

Alcoa, the 300th company on the Fortune 300, posted $9.3 billion in revenue last year, according to Fortune. This means that wearables were at least a bigger business than that. 

It also suggests that Apple makes more money on its headphones and watches than companies like Ebay, Netflix, and Salesforce made all last year. 

Apple hasn't decided yet where its new United States campus will be.

Earlier this year, in the wake of the passage of the big tax bill, Apple said it was building a new campus in the United States primarily for call-center workers.  This new facility could create as many as 20,000 jobs, Apple has said. 

Apple hasn't chosen the site of this new campus yet, Apple CEO Tim Cook said on Tuesday. 

"We're narrowing the site selection for a new U.S. campus, and we look forward to sharing more information on that later this year," Cook said. 

Know where Apple is looking? Email kleswing@businessinsider.com 

The HomePod speaker will get new features in a software update — and will go on sale in new countries.

Apple didn't reveal HomePod sales on Tuesday, although its accessories revenue was up sharply. But Cook did talk about what's coming next for the smart speaker. 

"It's currently available in the United States, the United Kingdom and Australia, and we're looking forward to adding new features to HomePod and introducing it to more markets around the world soon," said the chief executive. 

Facebook's annual F8 developers conference is typically chock full of splashy product and new feature announcements.

This year, the social media giant entered F8 under a cloud of high-profile scandals, including how the company deals with hate speech, election integrity, and data privacy. 

Even so, Facebook CEO Mark Zuckerberg and other executives unveiled a variety of new products at the 2-day event, going to great lengths to show that the company still has a few tricks up its sleeves despite all the recent distractions.

Here are the most important new products and features Facebook showed off at the conference: 

SEE ALSO: Facebook just gave a sneak peak at a big makeover coming to Messenger

Facebook gets into dating

Facebook will be integrating a feature for online dating directly into its main social-networking app. The feature, called Dating Home, will be opt-in and accessible by clicking on a small heart icon in the top right of the Facebook app.

Users who choose to create a Facebook dating profile will be able to chat with potential matches based on events and groups both are interested in. 

Lest you get the wrong idea, though, Zuckerberg says: "This is going to be for building real long-term relationships, not just hookups."

Learn more about how the dating service will work here.

Watch Party

Zuckerberg announced a new feature that lets users watch video while chatting with friends.

Showing off the new feature, he even poked fun at himself using his recent Congressional testimony in response to the Cambridge Analytica data privacy scandal.

Instagram and WhatsApp are getting group video chat

Users can already video chat with multiple people on Facebook Messenger, but the company announced that Instagram and WhatsApp, both of which are owned by Facebook, are getting the feature too. 

On Instagram, users will be able to minimize the video and continue video chatting while using Instagram simultaneously.

Warning: Spoilers ahead for season two, episode 20 of The CW's "Riverdale," titled "Shadow of a Doubt."

There was a lot of gunfire on "Riverdale" Wednesday night. 

From rounds of fire from the Black Hood, or an impostor Black Hood, to Reggie shooting Fangs, danger was lurking everywhere on The CW show. 

INSIDER worked with Archie Comics to reveal five references you might have missed.

When Veronica is explaining the mob families to Archie, she references the Borgia family and the Medici family.

Both were real families in the Italian Renaissance and were infamous rivals. 

The new sheriff, Michael Minetta, gets his name from the comics.

Mike Minetta, as he is known in the comics, is the newest iteration of The Hangman. This anti-hero comes from Dark Circle Comics — Dark Circle is also the name of Archie/Reggie's band of guys — which is an imprint of Archie Comics. 

Cheryl says Hal is about as stealthy as the Marshmallow Man.

When Betty tells Cheryl her theory about Hal being the Black Hood, Cheryl says her "pater"— Latin for father — "has all the stealth of a Marshmallow Man." 

The Marshmallow Man is a large monster featured in the "Ghostbusters" movies. 

The Las Vegas Golden Knights are one of the most compelling stories in sports right now.

In their first year, the expansion franchise has shown that it can compete with the best teams in hockey, rounding together a roster of players from every team across the league and quickly becoming a force in the NHL.

After winning the Pacific Division, the Golden Knights already have the best debut season for an expansion franchise in any major sport, but with a Stanley Cup berth on the visible horizon, Las Vegas is far from ready to settle.

Take a look below at how the team came together and turned a ragtag roster into one of the most dynamic teams in the NHL.

The Las Vegas Golden Knights' roster was initially put together through the expansion draft in June of 2017. All 30 NHL teams were allowed to protect one goalie, three defensemen and seven forwards, or one goalie and eight skaters. From there, the Golden Knights would build their team.

The protections prevented the Golden Knights from immediately nabbing most of the NHL's brightest stars, but the way that the draft was set up did allow for general manager George McPhee and majority owner Bill Foley to make some interesting and remarkably smart selections.

Probably the biggest get of the draft at the time for the Golden Knights was veteran goalie Marc-Andre Fleury. Fleury had won three Stanley Cups with the Penguins during his storied career in Pittsburgh, but was available in the expansion draft after the team chose to protect his successor Matt Murray instead.

Wealth often comes along with pretty expensive taste — especially when it comes to food and drink.

In order to determine where the high net worth individuals of the world like to dine, private jet lifestyle publication Elite Traveler surveyed its database of readers— all of whom are owners or users of private jets — on their favourite fine dining destinations across all seven continents.

As of last year, the magazine's readers had a median household income of $2.28 (£1.76) million and net worth of $41 (£32) million— so it's safe to say most of them are millionaires.

6,000 readers voted in order to produce the magazine's seventh annual list of the Top 100 Restaurants in the World.

Scroll down to see the top 25, ranked in ascending order.

SEE ALSO: This 26-year-old quit her law degree to start a luxury concierge club for bloggers and students — and now has 500 members paying up to £400 a month

25. Nihonryori RyuGin, Tokyo, Japan.

24. Le Calandre, Padua, Italy.

23. Jean-Georges, New York, USA.

• One out of every six retirees in America is a millionaire, according to a report from United Income.
• Handling finances for retirement can be difficult — the median level of wealth for retired Americans is about $200,000 — but people are living longer and costs are increasing.
• United Income CEO Matt Fellowes recommends creating an emergency fund and investing in index funds if you want to retire as a millionaire.

One out of every six retired Americans is a millionaire.

This is according to a report by online investing company United Income, which analyzed data from multiple sources, including the Federal Reserve Board and the US Bureau of Labor Statistics, to find out how retirees are faring now compared to previous generations. 

Average wealth for American retirees is $752,000 — which has more than doubled since 1989, the report found. Likewise, the rate of retired millionaires has more than doubled in the last 30 years. Fewer people are retiring in poverty and relying on minimum wage than ever before. The report says "the percentage of retirees living on the minimum wage or less dropped in half over the past 30 years."

Still, the median wealth for retirees is just over $200,000 — and people are living longer and costs are increasing. Many retirees end up relying on their monthly Social Security retirement benefits, about $1,400 on average. The Social Security Administration says the benefits account for one-third of retirees' income.

Retiring as a millionaire may seem like a difficult goal to accomplish. However, there are tricks that can help you get over the line so you can enjoy seven digit wealth when you stop working.

Matt Fellowes, the CEO of United Income shared his tips on how to retire a millionaire with Business Insider. Below are the eight best pieces of advice from Fellowes on how to be wealthy when you stop working. 

SEE ALSO: A self-made millionaire who retired at 37 says buying a home was 'probably the worst financial decision' he ever made

DON'T MISS: How many years it took the 23 richest people in the world to go from millionaire to billionaire

1. Save

One of the most common financial mistakes is not saving any money or not saving enough. Fellowes said that increasing your savings rate is "the single biggest thing you can do to increase the size of your nest egg in retirement."

Many factors can determine how much you should be saving, but it should be a significant amount if you expect to retire comfortably.

Fellowes said that the "optimal savings rates vary depending on your income, expected returns, retirement date, and desired lifestyle in retirement, but most people need to save 10-20% of their income for a comfortable retirement."

2. Invest the stock market

Investing obviously has a huge impact on future earnings and can be a major source of income in retirement. Finding the right investment mix is crucial to balance the right amount of risk with promise of high returns.

Fellowes recommends an investment portfolio weighted more in stocks than bonds. He notes that stocks have more risk, but by looking at the entire asset allocation and not just a single account, investors can use stocks to earn higher returns for retirement.

6. Don't try to beat the market

"Buy an index fund," Fellowes said.

Investing can be a major part of a robust retirement plan, but actively trying to outperform the market can spell trouble. Fellowes mentioned that from 2012-2017, 84% of professional money managers didn't outperform their benchmark indices.

For him, index funds are a good way to grow your finances with the market without the headache of actively trading.

Silicon Valley is home to some of the hottest venture capital firms worldwide. In the valley, the stakes are high. To be a successful investor, you need a keen business sense and attention to detail, a forward-thinking outlook, and a strategic eye for investment.  A handful of venture capitalists have acquired these skills early on, before the age of 30.

We've rounded up some of the top Silicon Valley investors under the age of 30 at leading firms. In addition to our own research, we reached out to VC firms and investors in Silicon Valley for nominations on noteworthy up-and-comers in the valley's tech scene to help come up with our final list. 

Here they are:

SEE ALSO: 30 AND UNDER: Rising stars in NY tech who find hot startup deals and manage millions of dollars

Saam Motamedi co-founded machine learning startup Guru Labs before joining Greylock Partners in 2016.

Jennifer Kaehms kicked off her career with a cold email to Canvas Venture's co-founder Rebecca Lynn. Now, she's involved with the firm's Stanford and UC Berkeley liaison programs and hosts events to help out junior members of venture firms.

Before joining Unshackled Ventures, Lucas Rocha worked with Dorm Room Fund, JetBlue Ventures, and Underscore.vc. So far, he's assisted in the deployment of more than $100 million in capital.

Nine members of the 115th US Congress have had to step down after allegations of sexual misconduct against them became public.

This wave of scandals stemmed from the #MeToo movement, the rising national conversation on workplace sexual harassment after highly publicized allegations of predatory behavior by prominent men in media and entertainment.

Here are the four Democrats and five Republicans who became embroiled in controversy all within the first of this Congress' two years:

SEE ALSO: 25 powerful men in politics and media accused of sexual misconduct in the wake of Harvey Weinstein

SEE ALSO: The 22 women who have accused Trump of sexual misconduct

Sen. Al Franken of Minnesota, Democrat

Franken resigned after a Senate ethics panel looked into accusations from eight women who said he had groped and forcibly kissed them.

The twice-elected senator announced his intent to resign after dozens of senators publicly called for him to step down in early December, and officially stepped down in early January.

"A couple months ago I felt that we had entered an important moment in the history of this country ... We were finally beginning to listen to women," he said in his resignation speech on the chamber floor. "Then the conversation turned to me."

Rep. Blake Fahrenthold of Texas, Republican

Fahrenthold resigned in April, months after reports revealed he spent $84,000 of taxpayer money to settle a 2014 sexual harassment claim from his former communications director.

The representative of Texas' 27th district said in December he would not seek re-election, and then in April issued a statement that he was ending his term early, and it was time to "look for new ways to serve."

Since 1997, the House has spent more than $17 million in taxpayer money to settle workplace disputes, including sexual harassment complaints.

Rep. John Conyers of Michigan, Democrat

Conyers resigned in December after 53 years in Congress. Buzzfeed News had reported he settled a female staffer's sexual harassment compliant in 2015 for more than $27,000. 

After the report, more women came forward with similar allegations against Conyers, and scores of his Democratic colleagues called on Conyers to step down.

People seem to love optical illusions.

There are the ones that make the rounds on the Internet —many of which end up going viral—and the ones that are created using just makeup.

And then there are the ones that you can actually visit IRL — natural sites, museums, and tourist attractions.

We rounded up 14 of the best optical illusions worth traveling for, from a mirror maze in California to an infinite tunnel of books in China to a gravity hill in Scotland.

Yangzhou Zhongshuge, Yangzhou, China

Book worms will love this library and store in China. One of its rooms boasts black mirrored floors and curved shelves that reach up to the ceiling, creating the illusion that this "tunnel" of books stretches on indefinitely.

Camera Obscura and World of Illusions, Edinburgh, Scotland

Pretty much every exhibit in this museum is dedicated to optical illusions. There's everything from the shrinking room (pictured above) to the mirrors maze and vortex tunnel.

The shrinking room is commonly known as an Ames Room, named after American ophthamologist Adelbert Ames, Jr., who created the first such room in 1946. When seen from a certain viewpoint (through a pinhole), the room appears cubic, even though it's actually shaped like a trapezoid, meaning its walls slant outward and its floor is on an incline. The room's far left corner is lower than the near right corner, which is why someone standing in one corner looks bigger than someone standing in another corner. This is also why someone in the room appears to be shrinking as they walk across the room.

 Click here to see what it's like to visit the trippy attraction.

Pedra do Telégrafo, Rio de Janeiro, Brazil

Tourists who take photos at Brazil's Pedra do Telégrafo look like they're risking their lives, but in reality, they're only standing a mere three feet or so off the ground.

However, if you frame the photo just right, you'll be able to get the cliff and the ocean below, but not the ground underneath the cliff, creating the illusion that you're on the edge of a major drop.

Click here to see what it's like to visit this popular Instagram spot.

• Billionaires don't always come from moneyed backgrounds.

• In fact, many famous billionaires actually grew up poor.

• From George Soros to Larry Ellison to Oprah Winfrey, here's a look at how some of the wealthiest people on the planet came up from nothing.

Billionaires aren't all born with silver spoons in their mouths.

In fact, many came from nothing at all.

The "rags-to-riches" trope may be a cliché, but it's one that's definitely grounded in reality for some famous billionaires.

Through extraordinary grit and perseverance, individuals across the globe have beat the odds and achieved their own rags-to-riches stories.

Here are 19 people who started off life poor and went on to become billionaires:

SEE ALSO: From fry-cook at McDonalds to waitress at Hooters, here are the unglamorous first jobs of 24 highly successful people

DON'T MISS: What Jeff Bezos, Elon Musk, and 23 other highly successful people were doing at age 25

Guy Laliberté was a fire-eater before founding Cirque du Soleil.

Net worth: $1.19 billion

At the beginning of his career, Laliberté had fire in his belly — literally. The Canadian-born circus busker played the accordion, walked on stilts, and ate fire.

Later on, Business Insider previously reported, he took a chance and flew a troupe from Quebec to Los Angeles without purchasing a return fair. The circus troup traveled to Las Vegas and became Cirque du Soleil.

Laliberté is now the CEO of Cirque de Soleil.

Kenny Troutt, the founder of Excel Communications, paid his way through college by selling life insurance.

Net worth: $1.41 billion

Troutt grew up with a bartender dad and paid for his own tuition at Southern Illinois University by selling life insurance. He made most of his money from phone company Excel Communications, which he founded in 1988 and took public in 1996. Two years later, Troutt merged his company with Teleglobe in a $3.5 billion deal.

He's now retired and invests heavily in racehorses.

Montpellier rugby club president and Entrepreneur of the Year Mohed Altrad survived on one meal a day when he moved to France.

Net worth: $2.6 billion

Born into a nomadic tribe in the Syrian dessert to a poor mother who was raped by his father and died when he was young, Altrad was raised by his grandmother. She banned him from attending school in Raqqa, the city that is now capital of ISIS. Altrad attended school anyway, and when he moved to France to attend university, he knew no French and lived off of one meal a day.

Still, he earned a PhD in computer science, worked for some leading French companies, and eventually bought a failing scaffolding company, which he transformed into one of the world's leading manufacturers of scaffolding and cement mixers, Altrad Group.

He has previously been named French Entrepreneur of the Year and World Entrepreneur of the Year.

It's not easy to keep a marriage going for any amount of time, but staying together happily for more than 50 years is a feat to truly be proud of. 

INSIDER asked real couples and their family members for photos of them back when they first fell in love and them today. What we discovered is that love keeps you looking good. 

Tim and Allana O'Shea

Tim, 71, and Allana, 70, will have been married for 50 years on March 16, 2018, but their first date was almost a disaster, their daughter Kelly told INSIDER. 

"My mother was not very impressed at first," Kelly wrote. "She spent hours getting ready for the date only to find out that my dad's idea of a date was taking a 6-pack of beer to the beach."

But things looked up later when Allana needed a date to a school dance and called Tim. They fell in love and decided to elope on March 16, 1968. Kelly said they are best friends and couldn't imagine life without the other. They recently bought a house at the Jersey Shore. 

Judy and Richard Columbus

Columbus, Ohio, is a special place for Judy, 78, and Richard, 79. Not only is it part of their namesake, but the couple met as students at Ohio State University. They've been married for almost 58 years and reside part of the year in New York and part in Palm Desert, California.

Ben Bryant and Elizabeth Hepburn

Ben Bryant and Elizabeth Hepburn met each other on July 26, 1967 at Summer stock, and were so enamored with each other that they married on November 25 of that year.

They were married for about 30 years when they eventually separated, then divorced in 1999.  But this story has a happy ending, as they eventually reconciled and remarried in 2010, a process that Ben wrote about in one of his memoirs: "Waiting For Elizabeth (A Love Story)." 

Schools in the US have changed a lot over the years. Chalkboards have been updated to whiteboards and Smart Boards. Notebooks and textbooks have been replaced with laptops and iPads. Segregation was overturned by the Supreme Court, and students are demanding safe schools free of gun violence from today's lawmakers.

Here's what schools have looked like from the 1940s to the present day.

1942

The students in a Seattle, Washington, high school duck for shelter beneath their desks during a mock air raid in 1942.

1944

Student Dan Moss reports the news to younger students in a 4A classroom in Chicago, Illinois, in 1944. On D-Day, older students heard broadcasts, rewrote them for primary students, and reported to classrooms throughout the school.

1947

A driving class at Chicago's Lane Technical High School learns the meaning of highway signs and signals in 1947.

Each spring, the Kentucky Derby attracts hundreds of thousands of people to Louisville's Churchill Downs. And while 20 fierce horses running the track at top speeds is the ultimate adrenaline rush, it's the fashion that truly makes this race a spectacle.

Everyone from celebrities like Kim Kardashian and members of the royal family to first-time attendees gear up in their best hats and spring ensembles. Sporting a headpiece at the event is believed to bring good luck, according to the Kentucky Derby website. And though the tradition was started by women, men have also started wearing more unique hats in recent years.

In preparation for the upcoming race on May 5, we've rounded up 60 of the wildest Derby hats that would give even the British royal family a run for their money.

This showstopping white feather hat was spotted on a Kentucky Derby fan in 2004.

The costume piece jazzed up the racing fan's white retro sunglasses.

Jessica Simpson also attended the 2004 race in a candy pink hat.

The singer and actress looked beach-ready in her oversized accessory.

Two fans tapped into the race's history by wearing rose hats at the 2005 event.

Red roses spilled over the sides of the hat on the left, while they were subtly incorporated to the black cowboy hat on the right.