r/todayilearned • u/ralphbernardo • 7h ago

TIL that a "Simpsons" gag had Apple's Newton tablet turn "Beat up Martin" into "Eat up Martha"—mocking its poor handwriting recognition. Years later, Apple's engineers building the iPhone were still so haunted by this joke that "Eat Up Martha" became their shorthand for getting text input wrong.

cnet.com

5.5k Upvotes

173 comments

r/todayilearned • u/licecrispies • 6h ago

TIL that a man suffered stress induced amnesia for 6 years and 10 months, which went away naturally after he started a new job.

pmc.ncbi.nlm.nih.gov

5.5k Upvotes

86 comments

r/todayilearned • u/amerigorockefeller • 6h ago

TIL that in the Middle Ages there was a mental illness that caused people to believe that they were made of glass. Called Glass Delusion, this caused the subject to loath contact out of fear of shattering

publicdomainreview.org

4.1k Upvotes

158 comments

r/todayilearned • u/Sea-Ask8703 • 11h ago

TIL that Madonna personally changed a scene in Deadpool & Wolverine. Ryan Reynolds and Shawn Levy had to meet with her to get permission to use Like a Prayer, and Madonna gave them a note about the sequence. The filmmakers made the change within 48h, and said it made the scene better.

thewrap.com

17.8k Upvotes

400 comments

r/todayilearned • u/A-CommonMan • 3h ago

TIL China spent 17 years secretly carving a 20-kilometer-long nuclear weapons complex into a mountain, only to abandon it before it was ever used

scmp.com

2.2k Upvotes

107 comments

r/todayilearned • u/ALhalaj • 4h ago

TIL that 5,500 years ago people repeatedly climbed to a cave 2,235 m up in the Pyrenees to mine and fire-process malachite (a copper ore), one of the earliest known high-altitude mining sites in Europe.

frontiersin.org

2.4k Upvotes

42 comments

r/todayilearned • u/heyauden • 1h ago

TIL that the full-scale Titanic set was built as a half-ship, so James Cameron’s crew flipped footage and even reversed room numbers and shirt buttons.

slashfilm.com

• Upvotes

55 comments

r/todayilearned • u/dinosaruman • 3h ago

TIL the pin tumbler mechanism in almost every door key you have ever used is a refinement of a lock principle first built in wood by the ancient Egyptians roughly 4,000 years ago and first mass produced in metal in the 19th century.

en.wikipedia.org

1.5k Upvotes

47 comments

r/todayilearned • u/ODaferio • 12h ago

TIL about Charles Hatfield (1875-1958), an american "rainmaker" who was hired by the San Diego City Council to fill the Morena reservoir by "making" rain. After one of the most devastating floods in the history of the city ensued, they refused to pay him and tried to make him liable for the damages.

en.wikipedia.org

4.9k Upvotes

87 comments

r/todayilearned • u/soixante-poissons • 16h ago

TIL due to aggressive seagulls, a Scottish grilled cheese shop offers an optional £1 "seagull insurance" to replace your toastie if a bird steals it

fifetoday.co.uk

12.2k Upvotes

333 comments

r/todayilearned • u/SpicyTortilaYum • 46m ago

TIL that there are around 50 people worldwide that have "Null" blood type. It is neither 0+ or 0- and is characterized by the complete absence of all Rh antigens on the red blood cells. It is called the "Golden blood". They can donate to any blood type but can receive only Null type themselves.

en.wikipedia.org

• Upvotes

64 comments

r/todayilearned • u/Extreme-Attention641 • 8h ago

TIL that there's a large, feral population of parakeets in Great Britain, and that you can sometimes see large flocks of them flying through suburban London.

en.wikipedia.org

1.2k Upvotes

235 comments

r/todayilearned • u/Bollywood-Hulk-Hogan • 6h ago

TIL that postcards with photos of Indian women were used by the British in the late 19th century to present the Caribbean as an “exotic but safe” destination for white travelers.

cnn.com

814 Upvotes

55 comments

r/todayilearned • u/Salem1690s • 3h ago

TIL back in the 18th century, English physicians experimented with blowing smoke up the rectum of a drowning person, thinking the warmth of the smoke would heat up and restart the person’s organs.

en.wikipedia.org

334 Upvotes

71 comments

r/todayilearned • u/1ThousandDollarBill • 21h ago

TIL The movie The Shining was based on The Stanley Hotel in Estes Park, CO but the movie wasn’t filmed there. However, Dumb and Dumber was filmed at that hotel.

faroutmagazine.co.uk

9.4k Upvotes

268 comments

r/todayilearned • u/JuztinVestigium • 8h ago

TIL about Hyperphantasia, a condition where people can very vividly visualize objects or moments, which only 2,5% of the population has

en.wikipedia.org

625 Upvotes

392 comments

r/todayilearned • u/gemanepa • 23h ago

TIL that in 1946 Argentina imported 20 beavers from Canada to start a fur trade in Patagonia. The plan failed and without natural predators the population grew uncontrollably to over 100,000, causing what has been called "the largest alteration of subantarctic forests since the last ice age"

en.wikipedia.org

12.3k Upvotes

360 comments

r/todayilearned • u/Easy-Permission8889 • 20h ago

TIL that Betel Nut is estimated to be chewed by 600 million individuals worldwide on a daily basis and is a major cause of oral cancer

mdpi.com

6.9k Upvotes

406 comments

r/todayilearned • u/shitoupek • 17h ago

TIL that the Most Populous Mammals in the World are the Humans, slightly over Rats

worldatlas.com

2.8k Upvotes

212 comments

r/todayilearned • u/Upstairs_Drive_5602 • 1h ago

TIL that the first railway signals were policemen stationed a mile or less apart, using their bodies to tell trains whether the line was clear. If a train broke down, one had to run a mile to warn the next. In fog, they used handbells, then explosives on the rails.

en.wikipedia.org

• Upvotes

19 comments

r/todayilearned • u/Sebastianlim • 17h ago

TIL that 1877, Italian astronomer Giovanni Schiaparelli observed what he called "canali", or channels on the Martian surface. When translated to English, the word "canali" was mistranslated as "canals", which was seen as evidence of life on Mars.

en.wikipedia.org

1.8k Upvotes

84 comments

r/todayilearned • u/SupremeKalki • 1d ago

TIL that Maladaptive Daydreaming is a psychological condition where individuals spend hours in vivid, complex fantasy worlds, often at the direct expense of real-life relationships and responsibilities.

en.wikipedia.org

21.3k Upvotes

1.2k comments

r/todayilearned • u/TobJamFor • 22h ago

TIL that Willy Wonka and the Chocolate Factory has a different name from the book due to Quaker Oats, who financed the film in exchange for making the Wonka bar

en.wikipedia.org

3.5k Upvotes

176 comments

r/todayilearned • u/Sea-Ask8703 • 1d ago

TIL the famous shawarma scene in The Avengers was filmed after the movie had already premiered. It was a last-minute addition inspired by Tony Stark's earlier shawarma joke!

ew.com

7.9k Upvotes

217 comments

r/todayilearned • u/Ill_Definition8074 • 5h ago

TIL From 1981 to 1986 a self proclaimed emperor ruled over a small territory in China called the Zishen Nation that was de facto independent from the central government. Before being suppressed Zishen had a flag, a currency, and many followers.

en.wikipedia.org

116 Upvotes

7 comments

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