Science & Tech
The Difference Between Total, Annular, Solar, and Lunar Eclipses
Solar eclipses may be classified as either total, in which the Moon completely covers the Sun, or annular, in which the Moon obscures all but an outer ring of the Sun.
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Is the Oedipus Complex Real?
Critics of Freud have noted that there is very little empirical evidence to prove the theory’s validity.
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Editor's Picks
Why Is the Sky Blue?
The science behind blue skies and beautiful sunsets.
Mandela effect
Mandela effect, popularized phenomenon in which a group of people collectively misremember facts, events, or other details in a consistent manner. Paranormal researcher and author Fiona Broome conceptualized the effect after discovering that she and others possessed strong, yet false, memories
Wee Worlds: Our 5 (Official) Dwarf Planets
Learn all about Pluto and its pals.
How Were Viruses Discovered?
Find out more about the scientists who first identified viruses.
7 Deadliest Weapons in History
From rocks to rockets.
The Real Science Behind Frankenstein
How Mary Shelley’s imagination came alive.
5 Common Misconceptions About Schizophrenia
Learn about five of the most common misconceptions about this highly stigmatized mental disorder in this Encyclopaedia Britannica Health & Medicine list.
Why do we get shots in the arm? It's all about the muscle
Immune cells, proximity to lymph nodes, and convenience—all argue for the arm’s muscles.
Spotlight: How Dinosaurs Became Birds
The story of how birds evolved from dinosaurs recently became more complicated with the discovery of Fujianvenator prodigiosus, a bird-like feathered dinosaur that did not fly. It lived at the same time as Archaeopteryx, which is often considered the first bird.
Quizzes
Name That Magnified Object!
Can you figure out what these common items are when they're extremely magnified?
Guess the Body Part Quiz
Taking this quiz requires guts.
Name That Thing: Science
Do you know the difference between a protractor and a compass?
Guess the Animal Eyes Quiz
Can you tell these creatures just by looking at their peepers?
Videos
Explore the phases of the moon and their effectiveness in tracking time
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Galleries
7 Wonders of the Natural World
Meteorites
Coral
Life
Tornadoes
The Solar System
Featured Categories
Biology
6 Cell Organelles
A quick refresher course in biology!
How Does the Human Body Maintain Its Temperature?
Human body temperature is regulated by the hypothalamus in the brain.
10 Ways of Looking at Cells
Learn about 10 cutting-edge microscopy tools that scientists are using to explore the internal structure of cells.
13 Questions About How the Human Body Works Answered
Blood, brains, lungs, skin, and more.
Astronomy
9 Ghostly Planets
Were they ever out there to begin with?
Why Are Planets Round?
There are a lot of strange things in the universe, so why are planets round instead of every shape imaginable?
How Fast Is the Universe Expanding?
Learn why the Hubble constant doesn’t seem to be very constant.
Telescopes: Seeing Stars
For the last 400 years, telescopes have changed our view of the universe.
Mathematics
al-Khwārizmī
Al-Khwārizmī, Muslim mathematician and astronomer whose major works introduced Hindu-Arabic numerals and the concepts of algebra into European mathematics. Latinized versions of his name and of his most famous book title live on in the terms algorithm and algebra. Al-Khwārizmī lived in Baghdad,
Unusual Counting Systems
In everyday life we use a base-10 counting system, but that is not something that has always been used in history.
Euclid
Euclid, the most prominent mathematician of Greco-Roman antiquity, best known for his treatise on geometry, the Elements. Of Euclid’s life nothing is known except what the Greek philosopher Proclus (c. 410–485 ce) reports in his “summary” of famous Greek mathematicians. According to him, Euclid
Aryabhata
Aryabhata, astronomer and the earliest Indian mathematician whose work and history are available to modern scholars. He is also known as Aryabhata I or Aryabhata the Elder to distinguish him from a 10th-century Indian mathematician of the same name. He flourished in Kusumapura—near Patalipurta