If you were handed three photos of a cheetah, an ostrich, and a porcupine, you could tell the difference. But what if you were only given the sounds these animals make?

One of them chirps. Another one squeaks. The third booms (that's the technical term). Do you know what sound belongs to which animal?

Booms and chirps aren't even the craziest sounds you'll hear in this compilation of shocking noises made by some of the world's most recognizable animals. Perhaps the most bizarre is a bird that sounds exactly like an old-school polaroid click camera.

A single animal can produce dozens of different sounds for different purposes. Here, we provide an example of one call from each. 

Unlike lions, jaguars, and other wild cats, cheetahs can’t roar. Instead, they chirp. That’s because the thyroid bone in their throat that they use to help generate sound is shaped differently from the same thyroid bone in wild cats that can roar. That’s also why your house cat can’t roar.

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Read more about why cheetahs chirp and lions roar.

Male ostriches are usually silent, but when it comes time to mate, they're very vocal. By filling a sac in their long necks with air, they produce a low-pitched, hollow, booming sound to let the female know they’re ready. Males in captivity will sometimes boom at visitors, too.

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Read more about how ostrich sounds in Ostrich Production Systems.

This is Teddy. He's part of the Texas traveling educational zoo, or Zooniversity. Wild porcupines are solitary creatures who don’t like to share. Teddy, although not wild, is no exception. When wild porcupines squabble over food or den space they sound a lot like Teddy in this video when asked to share his corn. (skip to the 26th second to hear him talk).

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Read more information about Teddy and porcupine behavior on National Geographic.

Above all else, Marie Curie was a scientist with remarkable insight. But to the science contemporaries of her time, Curie was a woman, who happened to study science.

At times she was overlooked for her achievements, which were laying the foundation for what we understand about radioactive behavior that, today, runs nuclear reactors, powers deep-space exploration, and drives an entire field of medicine, called radiology.

Through the shameful, sexist-derived neglect, Curie's intellect, wit, and drive pushed her toward miraculous discoveries that even the scientific community could not ignore for long.

Curie became the first scientist to earn two Nobel Prizes, had three radiology institutes erected in her honor, saw her eldest daughter win a Nobel Prize, and was revered by the most brilliant minds of our time, including Albert Einstein.

Today, she's celebrated as one of the greatest scientists in history. In honor of Madame Marie Curie's birthday this month, here's the incredible story of her struggles and victories in a world where women were shunned.

READ MORE: The amazing life of Albert Einstein, an underestimated genius whose childhood nickname was 'the dopey one'

SEE ALSO: This amazing 25-year-old woman helped bring Apollo astronauts back from the moon

Maria Salomea Skłodowska was born in Warsaw, Poland on Nov. 7, 1867. Here's one of the earliest known photos of her at the age of 16.

Born in Warsaw, Poland as Maria Salomea Skłodowska, her middle name originates from the Polish word "Salome," which is traced to the Hebrew word for "peace."

Maria would later adopt her husband's last name as well as the French translation of her first name, to become known as Marie Curie.

Source: NobelPrize.org

The Curie sisters were determined to study despite government bans on higher education for women.

Russia-dominated Poland was in the midst of a feminist revolution, but changes were slow-going.

Since women were still banned from higher education, Curie and one of her sisters joined the Flying University — an educational institution that admitted women— in the mid 1880s.

Source: American Institute of Physics

She eventually moved to Paris in 1891.

To continue her studies in chemistry, math, and physics, Curie studied at Sorbonne — the University of Paris at the time — where she eventually became head of the Physics Laboratory.

Source: NobelPrize.org

Most people will tell you they don't look forward to Sunday evenings.

In fact, a 2013 poll conducted by Monster.com found that a whopping 78% of surveyed adults worldwide experience the "Sunday night blues" on a regular basis.

Even if you love your job and typically look forward to getting back into the swing of things, "it's easy to feel a bit of trepidation on Sundays about the stresses waiting for you on Monday morning," writes Laura Vanderkam in her book "What The Most Successful People Do On The Weekend."

But there are some things you can do that will not only make your Sunday night more enjoyable, but can also set you up for a more productive and successful week.

SEE ALSO: The 27 jobs that are most damaging to your health

Spend quality time with your family, friends, and significant other.

Successful people know that their weeks will be jammed and that they are likely to be unavailable, says Roy Cohen, a career coach and author of "The Wall Street Professional's Survival Guide." So they make the most of their Sunday nights by spending time with their loved ones. 

This way, you won't have to feel stressed or guilty about not having so much time to spend with your loved ones throughout the work week. 

Plan something fun.

"This idea may be the most important tip," Vanderkam writes. "This extends the weekend and keeps you focused on the fun to come, rather than on Monday morning." 

Vanderkam quotes Caitlin Andrews, a librarian, who says her extended family gets together for dinner almost every Sunday, alternating houses. "It takes my mind off any Sunday night blues that might be coming on," Andrews says.

You might also make Sunday a movie or spa night, or you could join a Sunday night bowling league.

Ending the weekend on a high note helps you go into the week with a better attitude. 

Organize and plan for the week ahead.

The worst thing is walking into the office Monday to learn you have a big meeting you forgot about. 

That's why career coach Marsha Egan suggests looking at your calendar on Sunday night and setting goals and deadlines for the upcoming week.

The trick is to do this without stressing yourself out, she says.

I don’t know what y’all are drinking these days, but you’re dropping off some mighty fine nuggets around this blog lately! And I’m loving it! I think you need to merge together and come up with your own financial blog or something, haha …

But for now, you sit there and read this gem my new friend Mark posted and you enjoy it. He was kind enough to share his financial journey with us on last week’s book giveaway post, and it was a nice refresher of how this money stuff all comes together.

Check it out:

I’m a millionaire. Been investing in mutual funds for 40 years. Never made more then $70,000. Paid cash for everything. Still have an allowance of $100.00 a week. That is for gas and if I want something new. I’ve been debt free for 15 years. I often sit back and ask how I did this, and then remember my mom who at 16 worked in the ship yards during WW2, never graduated from HS, but gave me a book called Your Last Dollar. I still live off of $40,000 a year and no longer work, outside of a part time job as a coach as I love high school kids.

Look at that! An average guy making average money with not-so-average results. And people say it’s hard to become a millionaire, pssh … you just need a simple plan and some time.

Let’s go over all 11 tips he dropped in this jam-packed paragraph – did you catch them?

SEE ALSO: Remind Yourself Of This One Fact When You're Feeling Envious

1. Invest for the long haul.

Not for two or three or even ten years, but for decades. Mark did this successfully for over 40 years (longer than most of us have been alive — hah!) and he kept going through all the booms and busts and utter nonsense. You need this long term mentality so you don’t trick yourself into chasing the quick wins and get off track. It’s all about harnessing time.

2. Funds get the job done.

Yes you can try your hand at stocks and get your research/luck on and pray you hit the jackpot, but let’s face it – not even “professionals” get it right. For most people, sticking with mutual funds (or my personal preference – index funds– since the costs are much cheaper) are a safer bet. You won’t “beat the market” and have bragging rights amongst your friends, but matching it is better than underperforming it. And it’s one area I don’t mind being average.

3. It doesn’t matter how much you make – you can still save.

While $70,000 is surely a lot of money for most of us/the world, keep in mind it’s not the case when you’re nearing retirement. And even so, it probably took Mark 10-20 years to make it up to that level, so for decades he was making substantially less.

Regardless, putting money aside every paycheck no matter how much you make WILL add up over time and especially over 40 years. Do the best you can with what you’ve got, and then up it every time you get a bonus or raise or any other types of promotions. Mark is proof that any of us can become millionaires over time.

London's Heathrow Airport is one of the busiest hubs in the world and serves as a major point to connect traffic from Asia and Africa to North America.

As Britain's main international airport, Heathrow has been working hard to upgrade its facilities. In recent years, the airport has opened two new terminal buildings and has conducted significant renovations to others.

The greatest constraint on the airport, however, has been its lack of runways. Though more than 72 million passengers pass through Heathrow every year, the facility still operates using just two runways.

That's right, two. This makes operations for the airport quite challenging.

But if Heathrow's latest expansion plans are approved, things are about to change for the airport.

SEE ALSO: The Concorde flew across the ocean for the first time 42 years ago — here's what it was like

Though Heathrow's roots can be traced back as early as 1930, the foundations of the modern facility we know today were laid during World War II.

During the war, the facility was known as RAF Heston and featured a military control tower surrounded by a series of runways configured in a "Star of David" formation.

In 1946, the facility was reconfigured for civilian use.

If you enjoyed the music in anything made by Steven Soderbergh or Nicolas Winding Refn, you can thank Cliff Martinez.

The former drummer for bands like Red Hot Chili Peppers and Beefheart turned to a successful career as a film score composer with Steven Soderbergh’s 1989 debut feature “Sex, Lies, and Videotape.” Since then, his unique eerie electronica sound has found its was into the films of Refn (“Drive,” “Only God Forgives”), Joe Carnahan (“Narc”), and Harmony Korine (“Spring Breakers”).

With so many memorable works under his belt, including the second season of Soderbergh’s “The Knick,” now on Cinemax, Business Insider asked Martinez to make the tough decision of telling us his favorite scores he’s created. Here they are, with his words about them:

SEE ALSO: The cinematographer behind some of the most beautiful movies of all time gives his three favorites

1. “Solaris” (2002)

The ninth time Martinez teamed with Soderbergh was for this trippy sci-fi drama starring George Clooney investigating the crew at a research station orbiting a bizarre planet. Loosely inspired by the classic 1972 film of the same title, Soderbergh’s version bombed at the box office, but Martinez’s soothing score stands out.

“That was my first entry with a large orchestra,” he said. “And it was my first experience with a large studio. I was terrified.”

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2. “Traffic” (2000)

Two years before “Solaris,” Martinez was in his sweet spot for Soderbergh’s Oscar-winning “Traffic.” He provided a slick electronic feel that was in contrast to the gritty drug war the film profiled.

“That’s one of my favorites of my electronic scores,” Martinez said.

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3. “Contagion” (2011)

2011 was a good year for Martinez, and in it, he showed the diversity in his work. For Soderbergh’s “Contagion,” he delivered a thrilling score to match the terror of a world infected by a mysterious disease (the sound is very similar to what Soderbergh asked Martinez to create for “The Knick”).

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For decades, the Tokyo Motor Show was the premier show in Asia.

But with the rise of China as one of the world's largest auto markets, focus has been shifting towards shows in the Middle Kingdom. In reaction to this shift, Tokyo has turned itself into a techno-centric show with a focus of the future mobility.

In addition, the Tokyo Motor Show displays the latest offerings from Japan's numerous manufacturers and their pint-sized "kei" cars offerings, which are indigenous to the country.

The 2015 Tokyo Motor Show wrapped up earlier this month. Now, we're getting ready for the LA Auto Show, which pulls into the City of Angels at the end of this coming week. But let's have a look back at the zany exposition that Tokyo has become.

SEE ALSO: Check out the most expensive cars driven by the ultra-rich Chinese kids of LA

The biggest story to emerge from the Tokyo Show this year was Mazda's RX-VISION sports car.

The sleek concept represents Mazda's revival of its iconic RX rotary engined sports car. Mazda hasn't produced a rotary powered sports car since the cancellation of the RX8 in 2011.

Honda and its Acura luxury brand showed off the company's new NSX supercar — it's finally ready for production.

Some jobs intrinsically have more health risks than others. A nurse working in a hospital is more likely to catch an infectious disease than a lawyer working in an office, for example.

To rank the most unhealthy jobs in America, we used data from the Occupational Information Network, a US Department of Labor database full of detailed information on occupations.

In order to analyze jobs by their impact on workers' health, we took O*NET measures of six health risks in each of the 974 occupations in the database: exposure to contaminants; exposure to disease and infection; exposure to hazardous conditions; exposure to radiation; risk of minor burns, cuts, bites, and stings; and time spent sitting, since studies show that frequent inactivity shortens your lifespan. O*NET scores these factors on a scale from 0 to 100, with a higher score indicating an increased health risk.

Read on to find out which jobs have the most potential to damage your health.

Max Nisen contributed to an earlier version of this post.

SEE ALSO: The 25 highest-paying jobs for people who don't want to sit at a desk all day

DON'T MISS: Here's the most disproportionately high-paying job in every state

24 (tie). Radiologists

Overall unhealthiness score: 52.8

What they do: Examine and diagnose disorders and diseases using X-rays and radioactive materials.

Top three health risks:

1. Exposure to radiation: 87
2. Exposure to disease and infections: 85
3. Time spent sitting: 74

24 (tie). Metal-refining furnace operators and tenders

Overall unhealthiness score: 52.8

What they do: Operate or tend furnaces to melt and refine metal before casting or to produce specified types of steel.

Top three health risks:

1. Exposure to contaminants: 100
2. Risk of minor burns, cuts, bites, and stings: 96
3. Exposure to hazardous conditions: 94

24 (tie). Embalmers

Overall unhealthiness score: 52.8

What they do: Prepare bodies for burial in conformity with legal requirements.

Top three health risks:

1. Exposure to disease and infections: 83
2. Exposure to contaminants: 83
3. Exposure to hazardous conditions: 75

Many of us have probably been subjected to the judgment of our Baby Boomer parents, who wonder why younger generations are facing more debt and financial troubles.

I won't defend the spendthrift ways of Millennials and Gen-Xers, but the truth of the matter is that many things are simply more expensive now than they used to be.

Baby Boomers — those born between 1946 and 1964 — paid less for many of the things considered essential now.

Here are eight things that our Baby Boomer parents could afford more easily than we can.

SEE ALSO: 15 everyday expenses that eat away at your money

A home

Interest rates were probably higher for Baby Boomers, but the average price of a home was considerably lower, even after adjusting for inflation. The Case Shiller Home Price Index offers a good examination of home prices over time. Through most of the '60s, '70s, and '80s, the index was at about 120.

Now it's near 170, an increase of about 40%. During the housing bubble, it topped 220 — that was a near doubling of prices after inflation. No wonder so many of us got into unnecessary housing debt.

College

We've all heard stories about Baby Boomers who claim to have attended college for just a few hundred bucks a semester. Indeed, education was a relative bargain for our folks, who in 1975 paid the equivalent of $2,469 for a year of tuition and fees at a public university.

The cost is more than four times that today. The College Board reports that we experienced increases of 9.5% above inflation during the 2009-10 school year, and another 6.5% above inflation in 2010-11.

A car

A Baby Boomer may have bought his or her first car in 1970 for $3,450, or $20,781 in today's dollars. The average price of a car is now more than $30,000. The good news for today's car buyers is that quality of cars has improved, and there is a wider range of choices, including many at the more affordable end.

Boyan Slat is not your typical 21-year-old.

At an age when most people are still trying to figure out what they're going to do with their lives, the Dutch innovator is the head of The Ocean Cleanup, a nonprofit that's raised millions of dollars to put into action a plan that Slat devised.

His goal is to help clean up the Pacific garbage gyre — an enormous area of the ocean where swirling currents cause plastic from around the world to converge in huge patches.

This plastic isn't just ugly. Animals like sea turtles, seals, and birds eat it, which poisons them. And as it breaks down into little particles called microplastics, the debris ends up in fish that often enter our own food supply.

Here's the story of why Slat thinks he has a plan that could clean up much of this floating trash, despite some serious questions from scientists. 

Slat tells Tech Insider a diving trip he took when he was 16 years old inspired him to fight plastic in the ocean.

"I was diving in Greece, and I realized there were more plastic bags than fish, and I wondered why we couldn't clean it up," he says.

Back at school, Slat saw a presentation showing how currents take litter from all over the world and build it up in massive patches.

For the past month or so, I've used an Apple MacBook Air, Lenovo Yoga Pro 2, Dell XPS 13, and, most recently, a Microsoft Surface Pro 4 — the tablet Microsoft says can replace your laptop.

I don't know about that last part.

But when it comes to actually getting stuff done, I love using the Microsoft Surface Pro 4, which starts at $899, more than any other computer I've ever tried — including the MacBook Air.

Which is why it was so was heartbreaking when two consecutive Surface Pro 4 tablets died on me.

Here's why I loved using the Surface Pro 4, and what went wrong.

SEE ALSO: I tried Apple's new gigantic iPad Pro and was pleasantly surprised — but it's not for everyone

Just off the top, the Surface Pro 4 has some serious compromises — horsepower, ports, and the ability to use it on your lap come to mind. But in exchange you get a light, fast, high-performance touchscreen device for getting things done.

In lieu of a mouse, it comes with the super great Microsoft Surface Pen stylus for handwriting and precise movements.

Yet it doesn't really get to "Laptop Replacement" status without the $129 Surface Pro 4 Type Cover. Since the Surface Pro 4 comes with a full, no-holds-barred version of the Microsoft Windows 10 operating system, you need the keyboard to bring it up to its full potential.

A New York City apartment belonging to a noted couple in tech has sold for $2.1 million, the New York Observer reports. 

The former owners of the East Village home are Jeff Hammerbacher, an early Facebook employee and cofounder of Cloudera, and his wife Halle Tecco, founder of medical venture fund Rock Health.

They bought the apartment from Chloe Sevigny for $1.76 million in 2012. The couple then spent nine months renovating the space.

"We struggled to use color in our last apartment in San Francisco, which was all gray and navy, so we really wanted to experiment with color, pattern, and texture in this home," Tecco told Business Insider when the apartment first listed in June.

The buyer is reportedly Shana Randhava, executive director of the Estee Lauder Companies.

SEE ALSO: This Silicon Valley enclave is once again America's most expensive zip code

The one-bedroom apartment is located on the garden level of a townhouse in the East Village.

The entryway has some bright green patterned wallpaper.

The living room is filled with lots of texture and color. Its best features include a wall-length bookcase and a fireplace.

A few weeks ago, I took my very first cruise aboard Le Lyrial, a 122-cabin ship from the France-based line Ponant. I’d never been called to cruise before, but Ponant felt different.

The ships are small and elegant, with itineraries that tend toward the curious: a voyage to Antarctica, a sail up the Mediterranean (the one I took). But as a first-timer, I had no clue what to pack. What do you wear to a captain’s dinner? I wondered. And, do I still need an adaptor?

Enter Ponant’s COO, Navin Sawhney, who, with 20-plus cruises behind him, knows a thing or two about packing like skipper. Here’s what I learned.

SEE ALSO: The 15 best cruise ships in the world

Don't forget the umbrella.

"One thing that I have regretted not packing, twice, was a small, lightweight umbrella," Navin says. "You don't need it on a ship, of course, but you go on a ship to go ashore, where it might rain! And don’t forget that it’s also a great sun shield for warmer climates."

Bring bug repellent.

They won’t be a bother on the ship, but "for warm-weather destinations, like the coast of Central America, you should definitely bring a bug repellent for when you go ashore," he says. Navin prefers an organic lemon eucalyptus oil, which is easy to find and "smells much better than other repellents."

Bring ginger.

I never felt seasick, but there were a few rocky nights when I was relieved to have packed a bottle of ginger capsules, just in case. The ship can provide over-the-counter meds like Dramamine, but Navin recommends stashing a bag of Trader Joe’s ginger candy — portable and delicious.

The things you do today can influence your future. Good money decisions made now lead to a brighter, more financially secure tomorrow. Likewise, there are bad financial habits that can sink your future and lead to debt and devastation.

Every money decision you make everyday will influence the outcome of whether you'll be successful paying off debt or building wealth. As you lay your financial foundation, here are 10 bad financial habits to avoid:

SEE ALSO: The 12 dumbest things you can do with your money in your 30s — and how to avoid them

1. Spending money without tracking.

One of the biggest pitfalls likely to trip you up is spending without tracking. When we just try to keep track of it in our heads, we aren't accurate. You are much better off actively tracking your spending, or at least using a personal finance app that will do the tracking for you. If you don't know where your money is going, you're more likely to spend more than you earn, and that way leads to debt.

2.  Keeping up with the Joneses.

It's easy to fall into the trap of trying to buy thing things that other people have. Unfortunately, buying what you think you "should" buy forestalls thinking about your priorities. You could easily spend your way into debt and a poor financial future just by trying to "fit in" with your neighbors. Instead of keeping up with the Joneses, figure out what matters to you most, and stop spending on what's unimportant to you.

3. Spending everything you earn.

Even if you aren't exceeding your income, you still might be putting your financial future at risk. You should spend far less than you earn so that you can make saving a priority. Follow the old advice to "pay yourself first" and set money aside for the future and for a rainy day.

4. Using credit as an emergency fund.

One of the main reasons to set money aside for savings is so that you can build an emergency fund. Too many people rely on credit cards and home equity lines of credit for emergencies. Once you fall into this habit, it can be costly. Paying interest on your emergencies can lead to more debt later, and it also means that you are less able to handle problems in the future.

5. Habitually making late payments.

Your late bill payments can cause serious problems for your financial future. First of all, you run into late charges that can cost you money right now. However, repeatedly late payments can also result in a lower credit score. When you have a lower credit score, you will pay more in interest on your other loans, and you might even be unable to qualify for home loans or other loans that you might be interested in.

6. Neglecting your credit report.

It can be easy to forget to check your credit report, but you don't want to. Your credit report offers information about your financial habits, and can also provide you with warning in the even of identity fraud. Your credit can be trashed by fraudulent accounts that you know nothing about if you aren't careful. You don't want your first clue that there's a problem to be a rejection for a car or home you are trying to buy. You are entitled to a free report from each of the major bureaus every year by visiting AnnualCreditReport.com.

Adversity happens. That's a given. How you deal with it is the difference between merely surviving or thriving.

The ability to pick ourselves up when life knocks us down — resilience— is a crucial ingredient for coping well with challenges, catastrophes or even just the busy pace of modern life.

It's the ability to adapt successfully. And it's a skill worth developing, since it can help buffer stress, improve sleep, increase happiness, and promote good health.

So if you're someone who falls apart when your printer jams, keep reading.

Keep in mind that resilience is not a character trait we're born with; rather, it involves thoughts, behaviors, and actions that are learned and developed over time.

Building resilience starts by examining our thinking patterns, says Andrew Shatté, Ph.D., co-author of "The Resilience Factor" and chief science officer for the stress management website meQuilibrium.

"By the time we're about 20, we likely have developed a [largely unconscious] thinking style," Shatté says. Often that thinking focuses more on negative aspects of our lives rather than the positive ones, which allows us to get stressed out — flooded with emotions and a sense of uncertainty — which will stick with us, unless we take steps to change it.

Being resilient doesn't mean waltzing though life stress- and pain-free. Everyone experiences grief, sadness and a host of other emotions after any type of loss. It means "working through the emotions and effects of stress and painful events" without being crushed. Here are some strategies for keeping a cool head, bucking up, and rolling with the punches.

SEE ALSO: Former Delta Force officer reveals 12 leadership lessons he learned in one of the US military's most elite forces

DON'T MISS: The 27 jobs that are most damaging to your health

1. Notice your emotions.

Learning how to regulate our emotions is key to not getting mired in stress, explains Shatté. Notice what makes you angry, frustrated, sad, anxious, guilty, or embarrassed, he says. "Then ask yourself if the emotion is warranted. Oftentimes, our reactions are a reflection of faulty thinking rather than of reality.”

For example, Shatté says, some people may unconsciously have their antennae out for situations that make them feel inadequate. Once you take a step back and recognize that you're prone to certain negative emotions and thoughts, you can more objectively gauge whether you’re overreacting, or not. If you are, you can stop those thoughts dead in their track — and get on with your life.

2. Accentuate the positive.

It turns out Bobby McFerrin, the "Don’t Worry, Be Happy" guy, was onto something. Dwelling on past mistakes or being pessimistic during tough times won’t help you power through stressful events. Understanding that difficult times are only temporary and that you have the ability to get through them will help you maintain a positive outlook.

3. Live well.

Maintaining a healthy lifestyle is a great weapon for fighting stress. Relaxation techniques such as meditation, deep breathing, and yoga have been shown to reduce stress levels. Eating well, working out — and of course getting enough sleep — go a long way toward promoting resilience.

At least 120 people were killed and many more were injured in a series of shootings and bombings across multiple locations in Paris Friday evening. 

Residents of countries all over the world were shocked, alarmed, and saddened for the people of France. Online, the hashtag #PrayForParis took over social media, and a Paris peace sign symbol was posted by hundreds of thousands. 

Over the weekend, major cities around the globe paid tribute to the victims by brightly illuminating landmarks with the colors of the French flag.

SEE ALSO: Shootings and suicide bombings rock Paris in a night of terror that killed at least 120

The London Eye — London, United Kingdom

The Oriental Pearl TV Tower — Shanghai, China

San Francisco City Hall — San Francisco, California

When I tested 5 different apps on 5 consecutive nights back in September, I wasn't too impressed.

While some of the apps provided useful information and helped me plan for a better night's sleep, many of them just gave me performance anxiety, and no one needs more anxiety.

But, maybe the reason I wasn't happy with the apps is that they required a week or longer to "calibrate," or log enough entries to spot patterns in your sleep.

So I decided to try my favorite sleep app, Sleepbot, again for a whole week.

I thought it was great because it's free, pretty easy to use, allowed me to look at the audio and movement graphs separately, review the audio, take notes and choose a rating, and change my alarm ringtone.

When I started using Sleepbot, I was enthusiastic at first, but by the end of the week, that had changed.

Setting the alarm.

This is what you see when you open the app. Before you can start tracking your sleep, you have to choose what time you want to wake up, start sound recording and motion tracking, and turn on the smart alarm.

The smart alarm doesn't go off at a specific time — it's set to go off within a 30 minute span of your choosing.

The theory goes that you have a worse time waking up out of a deeper sleep then if it rouses you during a lighter sleep. The app watches your movement and sound recording and goes off during your most active time, when your sleep is lightest.

For the first night, I set the smart alarm to go off between 6:00 a.m. and 6:30 a.m., based on how active it determined I was in the that time frame from the motion tracking — which the app uses to determine what sleep state I am in.

Picking a song.

I like to customize my alarm so I wanted to pick a song that would set the tone for the week's experiment.

When I was testing sleep trackers before, I made a mistake of choosing a song that was too mellow and very easy to sleep through. So this time around, I picked the Lemonheads "Drug Buddy."

It's a fun, upbeat song that's not too jarring — a perfect start to the day.

Phone placement.

I also had to make sure my phone was able to both track my movements and record any sounds I made. I balanced it precariously on the edge of the bed, just next to my pillow.

Seventy years ago today, the branch of the United Nations focused on education, science, and culture — UNESCO— first ratified its constitution.

Since then humans have conquered polio, visited the moon, and made enormous leaps in fighting the spread of infectious disease.

Now, with a heavy heart in the wake of the November 13 Paris attacks, UNESCO's headquarters is celebrating the progress humanity has made since the organization's founding.  

Thanks to a partnership with Obscura Digital, visitors (and anyone watching from home) can check out large-scale projections of UNESCO photographs over the years, which are being thrown onto the face of its Paris headquarters today.

Welcome to the Mosaic of Change.

Tracing the history from 1945-present, the projections will show never-before-seen images from the UNESCO archive.

Chris Lejune, Obscura Digital's CEO, says the archive photos offer a brief history of how the world has changed in that time.

"We've reached such a connected place in human culture, but also a place where we're starting to have environmental issues and ongoing political issues," he tells Tech Insider.

There are many great personal finance books out there, but if you can't make the time to read, another option is listening to podcasts.

We compiled a list of informative, free podcasts that will answer all of your money-related questions, and help you understand the nuts and bolts of investing, saving, and spending.

Try tuning into one of these on your next commute if you're ready to start successfully managing your money.

SEE ALSO: 8 Resources That Will Make You Smarter About Investing

1. We Study Billionaires: The Investors Podcast

Hosts Preston Pysh and Stig Brodersen take a look into the lives of billionaires — including Richard Branson, Warren Buffett, and Mark Cuban — and study the books they read.

After determining the critical habits of the most financially successful individuals, they reveal their findings and insights on their show, "We Study Billionaires: The Investors Podcast." 

Don't miss:Episode 40: Richard Branson — Screw It, Let's Do It, where Pysh and Brodersen delve into the key concepts of the billionaire's book, "Screw It, Let's Do It," and discuss Branson's business mindset and his best advice.

Listen to We Study Billionaires here.

2. Listen Money Matters

This lively show, hosted by personal finance expert, Andrew Fiebert, and small business owner Thomas Frank, will keep you alert and laughing. The hosts offer actionable personal finance advice, and deliver it in a very raw and honest tone.

Don't miss: The 03/25/15 Episode: Being a Successful Penny Stock Trader, where Fiebert and Frank sit down with a trader who turned $12,000 into $4.2 million by trading penny stock.

Listen to Listen Money Matters here.  

3. Money Girl's Quick and Dirty Tips for a Richer Life

Author and personal finance expert Laura Adams keeps things brief and to the point in her under-10-minute podcasts. Despite their brevity, they're packed with digestible tips that will answer all of your burning money questions. Recent episodes include: "When you should avoid using a debit card,""Decisions Millennials must make to grow rich," and "5 FAQs about Roth retirement accounts."

Don't miss: Episode 403: 6 Risky Situations When You Should Avoid Using a Debit Card, where Adams explains when a credit card should always be used over a debit card, as well as your liability rights for debit and credit cards.

Listen to Money Girl here.   

Over the last few years, the smartphone has become so much more than a device we use to call people and send text messages.

But it's easy to get overwhelmed with the sheer number of apps — there are more than a million apps in Apple's App Store and Google's Play Store.

So I broke out the most useful apps I use every day. You should probably use them too.

Spotify is my go-to music app.

I've been a Spotify subscriber for years. The service gives me access to nearly any song (well, except maybe songs from Taylor Swift) on demand and allows me to download music for offline listening.

My favorite Spotify feature is Discover Weekly, a customized playlist that's updated each week with music the streaming service thinks you'll enjoy.

Cost: Free (with ads and limitations) or $9.99 per month. Available on both iOS and Android. 

Mint is a great way to keep track of spending.

Mint aggregates all of your financials — your bank accounts, credit cards, investments, and more — and puts them in one convenient place. The service helps you create budgets, produces reports that show what you spend your money on, and keeps a history of your purchases, which allows you to keep track of what you've been buying.

Cost: Free. Available on both iOS and Android.

I listen to WNYC every day.

WNYC's app gives you live streams of WNYC, the most-listened to public radio station in the US, so you can listen to "Morning Edition" and "All Things Considered" as they air in New York.

It also has a huge library of on-demand shows, like "Radiolab,""This American Life,""Fresh Air,""Marketplace,""The Moth," and more.

Best of all, the app has an offline listening mode that downloads programming for you based on your preferences, so you can listen without a cellular connection, like when you're on an airplane or subway.

Cost: Free. Available on iOS and Android.