Jessie Szalay

The concept of zero, both as a placeholder and as a symbol for nothing, is a relatively recent development.

The travels of Marco Polo from Venice to Asia opened up a whole new world to Europeans.

Metformin is a prescription drug used primarily in the treatment of type II diabetes.

Diclofenac is often used to treat pain, tenderness, swelling and stillness resulting from various types of arthritis.

Atorvastatin is a prescription medicine used to treat high cholesterol. It is sold under the brand name Lipitor.

Clindamycin is a prescription antibiotic commonly used to treat acne, vaginal infections and certain bacterial infections.

Amelia Earhart's disappearance during an attempt to fly around the world remains a mystery, but recent expeditions may have found clues to her fate.

Cavities, also referred to tooth decay or caries, are holes in the teeth. Cavities are the second-most common health disorder in the United States.

Broccoli, the green vegetable both reviled and revered by U.S. presidents, is a nutrient powerhouse.

Anne Frank was a teenage girl whose diary about her family's experiences while hiding from the Nazis continues to inspire and educate.

Giant sequoias and redwood trees grow hundreds of feet tall. They are found primarily in California.

The German zeppelin Hindenburg exploded 80 years ago, bringing an abrupt end to the age of airship travel.

The Caspian Sea is the Earth’s largest inland body of water. But is it a sea or a lake? The definition has international implications.

Lake Baikal, in southern Siberia, is the largest freshwater lake in the world by volume and the world's deepest lake.

Great Salt Lake is the largest lake west of the Mississippi River and the largest salt lake in the Western Hemisphere.

Crater Lake in Oregon, known for its vibrant blue color and purity, is the deepest lake in the United States.

The 1925 case against the teaching of evolution had a long-lasting effect on Americans' perception of science.

The Piltdown Man, claimed to be a "missing link," was one of the most successful and consequential hoaxes in scientific history.

The Feejee Mermaid was one of P.T. Barnum's earliest successes in showmanship, promotion and humbug.

For centuries, people have been trying to invent perpetual motion machines. The laws of physics, though, are working against them.

The Cardiff Giant, sometimes referred to as “America’s Biggest Hoax,” is a 10-foot-long stone figure that was touted as a petrified giant.

Plague is often associated with the Middle Ages, but the infamous disease wreaked havoc before and after that time, and continues to infect people today.

Free radicals are molecules with unpaired electrons. They rob other cells of electrons, causing damage and contributing to many diseases.

Grapefruit is a popular citrus fruit that is a terrific source of vitamins, fiber and other nutrients.

Tomatoes are healthful as well as tasty and versatile. They are especially lauded for their cardiovascular benefits.