What is blockchain? A visual explanation from a Stanford professor

Plato's famous allegory of the cave is a metaphor exploring the value of truth over ignorance.

Explore (and debunk) the world's most contagious misconceptions—from the 5-second rule to sugar rushes—on this interactive site. Click on each misconception for further evidence.

This interactive website features nearly 40,000 photos from Wikipedia for you to create visual mosaics with.

Check out some of the best books that can be read in a single day, with titles from Han Kang, Denis Johnson, Muriel Spark, and more.

Explore an interactive timeline of Earth's 4.5-billion-year history to visualize shifting landmasses and oceans, view the locations of significant asteroid impacts, and learn about major geological and biological events.

The tallest tsunami in recorded history was 524 meters (1,720 feet) high—taller than the Empire State Building—and occurred in Lituya Bay, Alaska, in 1958 after an earthquake dislodged a rockface into the water.

Hear 50 years of iconic hip-hop samples, the genre's foundational looped tracks.

Humans may have as many as 100,000 to 150,000 individual hairs on our scalps, growing at a rate of roughly 1 centimeter per month.

You may be better at spotting a lie when listening to a speaker's voice inflections rather than watching for facial and body cues.

George Lucas used Joseph Campbell's 'hero's journey,' a narrative structure that encompasses the common characteristics of multiple cultures' mythologies, to revise 'Star Wars.'

Watch a breakdown of the canine family tree that explains how foxes and wolves are related to our beloved household pets, like poodles and dachshunds.

One of the most famous portraits ever taken is 'Afghan Girl' (1984) by Steve McCurry, yet the subject Sharbat Gula went much of her life without being identified or benefitting from the image's success.

One of the most famous portraits ever taken is "Afghan Girl" by Steve McCurry. Sharbat Gula, the subject of the photo, was not credited until 2002 for her role in the famous National Geographic cover, and continued to live in poverty after the photo was taken.

Experience 14 billion years of important moments in world history with this scrollable interactive timeline.

If the moon were less than one-twelfth its current distance from Earth, the planet's tidal forces would overcome the moon's internal gravity, tearing it apart and forming a ring of debris.

Lesser-known phobias include turophobia, or the fear of cheese, and nomophobia, the fear of being without your cell phone.

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

Watch a visualization of what it would look like to move along Earth's surface as fast as the International Space Station, or about 23 times the speed of sound.

Semaglutides, which belong to a class of drugs called GLP-1s, are prescribed for weight loss in combination with diet and exercise because they trigger the release of the appetite-suppressing hormone incretin.

On a cruise ship, the average person uses about 50 gallons of water a day, which is treated by bacteria and onboard filtration systems, then stored until the ship can legally discharge the wastewater.

Author David Foster Wallace's 'This Is Water' speech provides guidance for adulthood.

See where your state ranked in an analysis of the best public school systems in the US.

Watch footage from the moments the Titanic wreck was discovered by a joint US-French research team in 1985.

Computer scientists first started trying to optimize dating using computers in the 1950s.

The US has discontinued a variety of different currency denominations over the years—including a $100K bill.

Simulations suggest that a paper airplane launched from the International Space Station would maintain its orientation and gradually descend for 3.5 days before chaotically tumbling down and burning up.

Humans tend to imagine aliens as humanlike, but that's probably unlikely. Three different hypothetical planets show how aliens' bodies could take many forms.

Watch Bruce Springsteen's 1985 performance of Woody Guthrie's 'This Land Is Your Land,' which he calls 'the greatest song ever written about America.'

Joan Didion interviewed The Grateful Dead in 1967, before they became music icons.

Watch the many different civilizations around the Mediterranean shift power from the year 2500 BCE to 0 BCE in this animated map.

Male pattern baldness accounts for more than 95% of hair loss in men and is characterized by thinning hair, hair loss, and a receding hairline.

Visualize the path of every solar eclipse from 1900 to 2099 and see what each looks like when observed from different locations on Earth.

Watch 4-plus decades of Pixar's opening logos.

Explore a collection of famous literary maps, including original images from 'Treasure Island,' 'The Swiss Family Robinson, ' and 'Walden.'

Explore the wineries of Napa Valley with an interactive map of its hundreds of wineries, vineyards, and tasting rooms.

Relax to a livestream of brown bears chilling in Katmai National Park in Alaska.

'Bibliotherapy' is of increasing interest as a way to improve mental health and help navigate complex life situations—with people immersing themselves in the experiences of fictional characters or nonfiction and self-help books to find relief and gain personal insights.

Emanuel Leutze's painting 'Washington Crossing the Delaware' is one of the defining images of the Revolutionary War.

Explore an interactive forecast of the future of the universe, from the return of Halley's Comet to the last light in the cosmos.

Sea stars are invertebrates—they lack a backbone—and while most exhibit pentametric radial symmetry due to having five arms radiating from a central disk, some can possess more than 40.

The Aztec Empire ruled over 80,000 square miles of central Mexico for nearly a century—until a small band of Spanish conquistadors brought it down in 1521.