Random Topics to Learn About

One press gives a random topic to learn about, with a question to start from.

Random Topics to Learn About

All 280
  1. LyrebirdHow well can a lyrebird copy the sounds it hears around it?

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How it works

Curious but out of ideas? The list holds 280 random things to learn about, from tardigrades to tulip mania, in eight groups that run from Animals and plants to Teach yourself.

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Random things to look up

The words on the card are the words to search: every topic is the title of an English Wikipedia article. Start with the question under the name, then follow the article's own links for an hour.

The most random things to research

Strange but true holds the oddest 60: a war against emus, a paradox about a buttered cat, a radio signal picked up once in 1977. For random topics to research for a class, The past and Science hold subjects with plenty written about them.

  • Stuck for random things to search up? Press three times and read about the one you know least.

Questions and answers

What are some fun random topics to learn about?

Try the Emu War, the Bouba/kiki effect, Rubber duck debugging, Singing sand or the Pizza theorem. Each sounds made up, and each has an article of its own to prove it is not.

What are some random things to teach yourself?

Shorthand, Origami, the Pigpen cipher, Bookbinding, Orienteering or the Circle of fifths. Teach yourself holds 34 topics that end in something you can do, not only something you know.

What are some random things to wonder about?

Every card carries a question: why the night sky is dark, how a falling cat lands on its feet, whether a ship with every plank replaced is the same ship. Wonder first, then read.

What are good random science topics to study?

Science holds 51, among them Aurora, Plate tectonics, Surface tension, Radiocarbon dating and Absolute zero. Animals and plants holds 48, from Bioluminescence to Slime mold.

What are some random math topics to study?

The Möbius strip, the Birthday problem, the Seven Bridges of Königsberg and the Tower of Hanoi each open with a puzzle and not a formula. Math and numbers holds 47.

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All 280 topics

Animals and plants 48

  • Animal echolocation How do bats and dolphins find things with sound?
  • Axolotl Why does this salamander keep its gills and stay in the water as an adult?
  • Bioluminescence Which living things make their own light, and what do they use it for?
  • Bird vocalization Why do birds sing, and how is a song different from a call?
  • Birdwatching How do you start telling birds apart by sight and by sound?
  • Bonsai How is a tree kept small in a pot for many years?
  • Bowerbird Which bird builds and decorates a structure only to win a mate?
  • Camouflage What are the different ways an animal hides in plain sight?
  • Carnivorous plant How does a plant trap an insect and take food from it?
  • Cat righting reflex How does a falling cat turn itself over to land on its feet?
  • Circadian rhythm What keeps a living thing on a clock of about 24 hours?
  • Cloud forest What grows in a forest that sits inside the clouds?
  • Compost How do food scraps and plant waste rot down into compost?
  • Convergent evolution Why do unrelated animals end up with the same body shape?
  • Deep-sea gigantism Why are some deep-sea animals far bigger than their shallow-water relatives?
  • Dendrochronology How do tree rings give the exact year a piece of wood grew?
  • Domestication of the dog How did wolves become dogs?
  • Extremophile What lives in hot springs, in ice and in very salty water?
  • Fairy ring Why do mushrooms grow in a circle?
  • Galápagos Islands Why do these islands have animals found nowhere else?
  • Honeycomb theorem Which grid divides a flat surface into equal areas with the least edge?
  • Hummingbird How does a hummingbird hover and fly in any direction?
  • Hydroponics How do plants grow with no soil?
  • Kelp forest What is a forest under the sea made of, and who lives in it?
  • Lichen Which living things join up to make one lichen?
  • Living fossil What makes a species a living fossil?
  • Lyrebird How well can a lyrebird copy the sounds it hears around it?
  • Mangrove How do trees live with their roots in salt water?
  • Mantis shrimp How hard does a mantis shrimp strike, and what do its eyes see?
  • Metamorphosis How does one animal change its whole body shape as it grows up?
  • Mimicry Why do some harmless animals look like dangerous ones?
  • Monotreme Which mammals lay eggs?
  • Mycorrhiza What do a fungus and a plant's roots give each other?
  • Photosynthesis How does a leaf turn light, water and air into sugar?
  • Pollination Which animals carry pollen besides bees?
  • Seed dispersal How do plants send their seeds away from the parent plant?
  • Slime mold What is a slime mold, and why was it once grouped with the fungi?
  • Socotra Why does this island have trees that grow nowhere else?
  • Swarm behaviour How do thousands of birds or fish move as one without a leader?
  • Symbiosis How do two species live together so closely that both gain?
  • Tardigrade How does an animal usually no more than half a millimeter long survive being dried out?
  • Terrarium How does a garden sealed in a jar water itself?
  • Tide pool What lives in the rock pools the sea leaves behind at low tide?
  • Tool use by non-human animals Which animals use tools, and what do they use them for?
  • Tundra Why do so few trees grow on the tundra?
  • Turritopsis dohrnii Which jellyfish can turn back into its young form?
  • Watermelon snow Why does some mountain snow turn pink?
  • Wombat Why are a wombat's droppings shaped like cubes?

Science 48

  • Absolute zero What is the coldest that anything can be?
  • Amateur astronomy What can you see in the night sky with no telescope at all?
  • Atoll How does a ring-shaped island form?
  • Aurora What makes the northern and southern lights?
  • Ball lightning What are the glowing balls people report during thunderstorms?
  • Black hole What is an event horizon, and why can light not get out?
  • Buoyancy Why does a steel ship float when a steel nail sinks?
  • Cenote What is a cenote, and how does one form?
  • Dead Sea Why do people float so easily in the Dead Sea?
  • Doppler effect Why does a siren drop in pitch as it passes you?
  • Dwarf planet What makes a world a dwarf planet and not a planet?
  • Exoplanet How do astronomers find planets around other stars?
  • Fjord How is a fjord made?
  • Geomagnetic reversal Has magnetic north always been in the north?
  • Geyser Why does a geyser erupt?
  • Giant's Causeway What made about 40,000 stone columns on a seashore?
  • Greenhouse effect How does the air keep the Earth warmer than it would otherwise be?
  • Habitable zone How far from a star could a planet keep liquid water?
  • Hot spring What heats the water of a hot spring?
  • Ice age What starts an ice age, and what ends one?
  • Karst How does water carve caves and sinkholes out of rock?
  • Kuiper belt What lies in the belt of icy bodies beyond Neptune?
  • Light-year How far is a light-year, and why is it a distance and not a time?
  • Meteor shower Why do meteor showers come back at the same time each year?
  • Midnight sun Where does the sun stay up all night in summer?
  • Mirage Why does a hot road look wet from far away?
  • Mpemba effect Can hot water freeze faster than cold water?
  • Neutron star What is left when a giant star collapses?
  • Ocean current What drives the great currents of the sea?
  • Olbers' paradox If there are stars in every direction, why is the night sky dark?
  • Pangaea What did the world look like when the continents were joined as one?
  • Periodic table Why is the table of the elements laid out in the shape it has?
  • Petrichor What makes the smell of rain on dry ground?
  • Plate tectonics What moves the continents, and how fast do they go?
  • Radiocarbon dating How does carbon tell the age of a bone or a piece of wood?
  • Rain of animals Can it really rain fish or frogs?
  • Sailing stones How do rocks slide across a desert floor with nobody pushing?
  • Singing sand Why do some sand dunes hum or boom?
  • Snowflake Why do snowflakes have six sides?
  • Solar eclipse Why is there not a solar eclipse at every new moon?
  • Sonic boom What makes the bang when a jet flies faster than sound?
  • Stalactite How do icicles of rock grow from a cave roof?
  • State of matter What states of matter are there besides solid, liquid and gas?
  • Static electricity Why does a rubbed balloon cling to a wall?
  • Superconductivity What happens when a material loses all electrical resistance?
  • Surface tension How can an insect walk on water?
  • Weather lore Is there any truth in 'red sky at night'?
  • Wow! signal What was the radio signal of 1977 that was never heard again?

How things work 42

  • 3D printing How is a solid object built up one layer at a time?
  • Active noise control How can a sound be cancelled by another sound?
  • Algorithm What is an algorithm, and where does the word come from?
  • Archimedes' screw How does turning a screw lift water uphill?
  • Bimetallic strip How do two metals joined together bend when they get warm?
  • Binary number How do you count using only 0 and 1?
  • Boomerang Why does a boomerang come back?
  • Check digit How does the last digit of a code catch a typing mistake?
  • Data compression How does a file get smaller without losing anything?
  • Differential (mechanical device) How do a car's wheels turn at different speeds in a corner?
  • Electric battery How does a battery turn chemicals into electricity?
  • Escapement What makes a clock tick?
  • Flush toilet How does a toilet flush without a motor?
  • Fresnel lens How does a lighthouse lens send its light so far?
  • Hot air balloon How do you steer a balloon that has no engine?
  • Hydroelectricity How does falling water make electricity?
  • Igloo How does a house made of snow keep people warm?
  • Jacquard machine How did punched cards tell a loom which pattern to weave?
  • Light-emitting diode How does an LED make light without a glowing wire?
  • Lock (water navigation) How does a boat go uphill?
  • Microwave oven How do microwaves heat food?
  • Optical fiber How does light carry a message through a thread of glass?
  • Optical telegraph How were messages sent from tower to tower before electricity?
  • Paper plane What makes one folded paper plane fly farther than another?
  • Pin tumbler lock How does the right key let a lock turn?
  • Pinhole camera How does a box with one tiny hole make a picture?
  • Polder How is new land won from the sea?
  • Public-key cryptography How can two strangers agree on a secret while everyone listens?
  • Roman aqueduct How did Rome bring water to its cities without pumps?
  • Rubber duck debugging Why do programmers explain their code to a toy duck?
  • Sewing machine How does a sewing machine make a stitch from two threads?
  • Soap How does soap lift grease that water alone cannot?
  • Submarine How does a submarine sink and rise on purpose?
  • Suspension bridge How do cables hold up the deck of a bridge?
  • Terrace (earthworks) How do farmers grow crops on a steep mountainside?
  • Touchscreen How does a sheet of glass know where your finger is?
  • Traffic light What decides when a traffic light changes?
  • Transatlantic telegraph cable How was a cable first laid across the floor of an ocean?
  • Uncanny valley Why are robots that look almost human unsettling?
  • Water clock How did people tell time with water?
  • Wind turbine How do turning blades become electricity?
  • Zipper How do two rows of teeth lock together and come apart again?

The past 46

  • Abacus How do sliding beads add and multiply?
  • Angkor Wat Who built Angkor Wat, and what was it for?
  • Antikythera mechanism What was a geared machine from ancient Greece built to work out?
  • Bayeux Tapestry What story does an embroidered cloth nearly 70 meters long tell?
  • Çatalhöyük What was life like in a very large settlement of the New Stone Age?
  • Cave painting What did people paint on cave walls, and how long ago?
  • Coffeehouse Why did coffeehouses become places to trade news and ideas?
  • Cuneiform How did people write by pressing a reed into clay?
  • Dancing plague of 1518 Why did people in one city dance for days on end?
  • Derinkuyu underground city Why was a city dug many levels deep into soft rock?
  • Domesday Book Why did a king send men to survey every shire of England?
  • Egyptian hieroglyphs How do the picture signs of ancient Egypt spell out words?
  • Emu War Why did soldiers take on emus in Australia in 1932, and who came off better?
  • Göbekli Tepe Who raised huge stone pillars here more than 10,000 years ago, and what for?
  • Great Stink How did one smelly summer give London its sewers?
  • Great Zimbabwe Who built the stone city of Great Zimbabwe?
  • Hanging Gardens of Babylon Did the Hanging Gardens of Babylon ever exist?
  • Hanseatic League How did a league of merchant towns come to dominate trade on the Baltic Sea?
  • Heraldry What do the colors and animals on a coat of arms stand for?
  • Ice trade How was ice shipped and sold around the world before freezers?
  • Indus Valley Civilisation What do we know of a civilization whose writing nobody can read?
  • Industrial Revolution Why did the Industrial Revolution begin in Britain?
  • Late Bronze Age collapse Why did several civilizations fall at about the same time?
  • Library of Alexandria What became of the most famous library of the ancient world?
  • Longship How was a Viking ship built to cross open sea and sail up rivers?
  • Machu Picchu Why was a city built on a mountain ridge, and who lived there?
  • Magna Carta What did the charter of 1215 make a king promise?
  • Maya script How was the writing of the Maya worked out?
  • Moai How were the great stone figures of Easter Island moved?
  • Nazca lines Who drew giant figures on the desert floor, and how?
  • Petra How was a city carved out of rock?
  • Pig War (1859) How did one pig nearly start a war in 1859?
  • Polynesian navigation How did sailors find small islands across an ocean by the stars, the birds and the swells?
  • Quipu How did the Inca keep records with knotted cords?
  • Roman roads How were Roman roads built to last?
  • Rosetta Stone How did one carved stone unlock the writing of ancient Egypt?
  • Seven Wonders of the Ancient World Which of the seven wonders is still standing?
  • Sexagesimal Why are there 60 minutes in an hour?
  • Space Race What were the firsts of the race into space?
  • Spice trade Why were spices worth sailing around the world for?
  • Stonehenge Who built Stonehenge, and where did its stones come from?
  • Sutton Hoo What was found inside a ship buried under a mound in England?
  • Terracotta Army Why was an army of clay soldiers buried underground?
  • Tulip mania How high did the price of a tulip bulb climb before it crashed in 1637?
  • Voynich manuscript Why can nobody read this old illustrated book?
  • Year Without a Summer Why did 1816 have no proper summer?

People and places 30

  • Antarctic Treaty System Who owns Antarctica?
  • Atacama Desert How dry is the driest desert outside the poles?
  • Catatumbo lightning Where does lightning light the sky on 140 to 160 nights a year?
  • Constructed language Why do people invent whole languages?
  • Continental divide What decides which ocean a raindrop ends up in?
  • Darvaza gas crater How did a crater in a desert come to burn for decades?
  • Enclave and exclave Which pieces of one country lie wholly inside another?
  • Esperanto Why was a whole new language created in 1887, and who speaks it now?
  • Ghost town Why does a whole town empty out?
  • Lake Baikal What makes Lake Baikal the deepest lake in the world?
  • Language isolate Which languages have no known relatives?
  • Lingua franca How do people with different mother tongues talk to each other?
  • Map projection Why is every flat map of the world wrong somewhere?
  • Mariana Trench How deep is the deepest part of the ocean?
  • Microstate Which are the smallest countries in the world?
  • Mount Everest How was the height of the highest mountain measured?
  • Oasis Where does the water of an oasis come from?
  • Phantom island Which islands stood on maps for years but were never there?
  • Prime meridian Why does the line of zero longitude run through Greenwich?
  • River delta Why does a river split into many arms where it meets the sea?
  • Sahara Was the Sahara always a desert?
  • Salar de Uyuni What is the world's largest salt flat like?
  • Svalbard Global Seed Vault Why are seeds from around the world kept inside an Arctic mountain?
  • Toponymy How do places get their names?
  • Trap street Why would a mapmaker draw a street that does not exist?
  • Tristan da Cunha What is life like on an island called the most remote inhabited place in the world?
  • Vexillology What do people who study flags look at?
  • Whistled language Which languages can be whistled across a valley?
  • Writing system How many kinds of writing are there, and how do they differ?
  • Yurt How is a round tent built to be packed up and moved?

Math and numbers 36

  • Benford's law Why do so many real-world numbers begin with the digit 1?
  • Birthday problem How many people must be in a room before two probably share a birthday?
  • Collatz conjecture Which simple rule has nobody proved always ends at 1?
  • Fibonacci sequence What rule makes each Fibonacci number, and where does the sequence turn up?
  • Four color theorem Why are four colors enough to color any map?
  • Fractal Which shapes show the same kind of detail however far you zoom in?
  • Golden ratio What number is the golden ratio, and how do you draw it?
  • Googol How big is a googol?
  • Hairy ball theorem Why can you never comb a hairy ball flat without a tuft?
  • Ham sandwich theorem Can one straight cut halve the bread, the ham and the cheese at once?
  • Hilbert's paradox of the Grand Hotel How does a full hotel with endless rooms fit one more guest?
  • Infinite monkey theorem Could a monkey hitting keys at random ever type a whole play?
  • Interesting number paradox Is there such a thing as an uninteresting number?
  • Kaprekar's routine Which four-digit number does one subtract-and-repeat routine keep ending on?
  • Knot theory How do mathematicians tell one knot from another?
  • Leap year Why does February gain a day, and which century years miss out?
  • Magic square How do you fill a square so every row, column and diagonal adds up the same?
  • Mental calculation Which tricks let people do big sums in their heads?
  • Möbius strip How can a strip of paper have only one side?
  • Palindrome Which words, sentences and dates read the same backwards?
  • Pascal's triangle What patterns hide in a triangle of added-up numbers?
  • Perfect number What makes 6 and 28 perfect numbers?
  • Pizza theorem How do two people share a pizza fairly when the cuts miss the center?
  • Platonic solid Why are there only five perfectly regular solids?
  • Potato paradox How much do potatoes weigh after drying from 99 to 98 percent water?
  • Prime number Why is there no largest prime number?
  • Prisoner's dilemma Why might two people both choose badly when each one chooses sensibly?
  • Pythagorean theorem How many ways are there to prove the rule of the right-angled triangle?
  • Seven Bridges of Königsberg Can you cross each of seven bridges exactly once in one walk?
  • Sieve of Eratosthenes How do you sift the prime numbers out of a list?
  • Substitution cipher How do you write a secret message by swapping letters, and how is it broken?
  • Tessellation Which shapes cover a floor with no gaps and no overlaps?
  • Tower of Hanoi How many moves does it take to shift a stack of discs?
  • Travelling salesman problem What is the shortest round trip through a list of towns?
  • Triangular number Which numbers of dots make a triangle?
  • Zeno's paradoxes How does a fast runner ever catch a tortoise with a head start?

Strange but true 8

  • Bouba/kiki effect Why do most people give the same made-up name to the same shape?
  • Buttered cat paradox What happens if buttered toast is strapped to the back of a falling cat?
  • Déjà vu Why does a new place sometimes feel as if you have been there before?
  • Earworm Why does a tune get stuck in your head?
  • Frequency illusion Why does a word you just learned seem to turn up everywhere?
  • Pareidolia Why do we see faces in clouds and in everyday objects?
  • Ship of Theseus If every plank of a ship is replaced, is it the same ship?
  • Will-o'-the-wisp What were the lights that travelers saw over marshes at night?

Teach yourself 22

  • Bookbinding How are loose pages sewn and glued into a book?
  • Chess opening Why do chess players spend years studying the first moves?
  • Circle of fifths How does one circle show every musical key and its sharps or flats?
  • Color theory Which colors go together, and why?
  • Cryptic crossword How does a cryptic clue hide two routes to one answer?
  • Cyanotype How do you print a blue picture with sunlight?
  • Flip book How do drawings on a stack of pages turn into a moving picture?
  • Haiku How is a haiku counted, and what goes in one?
  • Letterboxing (hobby) How do you follow clues to a hidden box and stamp your logbook?
  • Lip reading How much of speech can be read from the lips alone?
  • Mind map How do you draw your notes around one central idea?
  • Orienteering How do you find your way with only a map and a compass?
  • Origami What can be folded from one square of paper with no cuts?
  • Paper marbling How do floating inks print swirls onto a sheet of paper?
  • Pigpen cipher How does a grid of lines and dots stand in for the alphabet?
  • Rule of thirds Where should the subject sit in a photograph?
  • Shorthand How do people write as fast as someone talks?
  • Sleight of hand How do magicians make a coin vanish with fingers alone?
  • Sourdough What lives in a sourdough starter and makes bread rise?
  • Spaced repetition When should you go back over a fact so that it sticks?
  • Stop motion How do you make a clay figure seem to move on film?
  • Ventriloquism How do you speak with your lips barely moving?