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

If a source of music traveled past someone at twice the speed of sound, assuming sufficiently sensitive hearing and powerful equipment, they would hear the music backward.

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.

Cats have a mutation that prevents them from tasting sweetness, and goldfish rank among the world's supertasters.

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

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

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.

There are up to 100 trillion microbes in the gut, and maintaining the relative balance in this ecosystem is important for our health.

Explore Lewis and Clark's 8,000-mile journey in Google Earth.

Watch a two-year time-lapse of a pinecone seed transforming into a pine tree.

Explore the history, structure, and species of Australia's Great Barrier Reef with this interactive journey narrated by Sir David Attenborough.

Rapid intensification is the increase in a hurricane's sustained wind speed by at least 35 miles per hour within 24 hours, which can strengthen it by up to two categories.

The animatronic shark from 'Jaws' was a complex machine called 'Bruce.'

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

Stonehenge was built using giant wooden rollers and precisely carved tongue-and-groove joints to lock the stones in place.

This short animation shows how human beings managed to lug 30-ton stones over miles of prehistoric English countryside and stand them up The Stone Age engineering involved using giant wooden rollers and carving precisely interlocking tongue-and-groove joints to hold the heavy stones in place.

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.

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

Washing dishware before putting it in a dishwasher may reduce the appliance's effectiveness because it dynamically adjusts wash time and temperature based on a sensor that detects dirtiness.

Examine this captivating animation 'building' a human—illustrating the roughly 40 weeks of fetal development.

'Golden blood' is the rarest blood type in the world—fewer than 50 people are known to have it.

Robert Smalls escaped slavery by piloting a stolen Confederate ship to freedom, then became an influential Black political leader during Reconstruction.

Explore 3D models of some of the most dangerous viruses, allowing us to understand these and other pathogens in new ways.

The final shots of the Civil War were fired in the Arctic over 2 months after the South's surrender.

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

Explore how temperatures compare to historical averages in cities worldwide with this interactive global monitor.

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

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

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.'

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.

As part of the up to 15 pounds of seafood they consume daily, sea otters eat urchins that feed on kelp forests—sources of shelter and food to over 800 species—thereby making the marine mammal a keystone species.

A dog's nose can be up to 100,000 times more sensitive than a human's, and each possesses a secondary organ for smelling, which helps learn about other dogs when they sniff each other's butts.

Listen to audio clips from Hoover, a harbor seal named after its insatiable appetite, who learned to say English phrases such as 'hello there' and 'come over here.'

'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.

Watch Dr. Laurence Peter explain his 'Peter Principle,' which states that people are promoted to their level of incompetence and explains why bosses aren't always good at their jobs.

There are 'YouTube camps' that teach children how to create content for the video platform.

Find out how important you are to AI tools when they generate text responses with this tool, which estimates the weights of people's names.

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.

Pregnancy makes someone more attractive to the mosquito species that transmits malaria.

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

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.