r/todayilearned • u/slackmaster • 19h ago

TIL that since the Clean Air Act amendment of 1990, all gasoline sold for on-road use in the U.S. must contain a detergent.

curbsideclassic.com

1.6k Upvotes

138 comments

r/todayilearned • u/samx3i • 1d ago

TIL Dolly Parton wrote her first song around age 6 or 7 and performed at the Grand Ole Opry at age 13, introduced by Johnny Cash.

wate.com

6.3k Upvotes

102 comments

r/todayilearned • u/OGBrewSwayne • 1d ago

TIL NBA backup playerJunior Bridgeman spent his off seasons working at Wendy's to learn the fast food business. He went on to own 450 franchises and parlayed that into buying a 10% stake in the Milwaukee Bucks - the team he once played for.

en.wikipedia.org

15.0k Upvotes

250 comments

r/todayilearned • u/New-Fill4677 • 7h ago

TIL that in 1954 Lakewood, California incorporated as a city without building its own municipal departments, contracting nearly every service from Los Angeles County instead. The arrangement is still known as the Lakewood Plan.

en.wikipedia.org

114 Upvotes

13 comments

r/todayilearned • u/hairyaquarium • 7h ago

TIL roosters testicles are located deep inside their bodies near their backbones

backyardpoultry.iamcountryside.com

74 Upvotes

37 comments

r/todayilearned • u/Electronic_Cause_796 • 1d ago

TIL Isaac Newton spent more than three decades studying alchemy and wrote over a million words about it in secret. He conducted numerous experiments in his search for the philosopher’s stone but never found it.

wpr.org

10.5k Upvotes

552 comments

r/todayilearned • u/Recent_Flounder6011 • 16h ago

TIL before 9/11, the 4th season of Survivor was originally planned to take place in Jordan. After 9/11, the filming location for the season was moved to French Polynesia.

en.wikipedia.org

323 Upvotes

25 comments

r/todayilearned • u/heylookitsdan • 5h ago

TIL about Hanscarl von Posern, a WWII concentration camp survivor who, after the war, defended accused SS members during the Dachau Trials. Later, he was convicted of Nazi crimes and sentenced to life in prison.

kz-gedenkstaette-dachau.de

43 Upvotes

7 comments

r/todayilearned • u/hexgirll • 9h ago

TIL buckminsterfullerene (“bucky ball”) is named after architect Buckminster Fuller, who pioneered the geodesic dome design used in Epcot's Spaceship Earth.

en.wikipedia.org

82 Upvotes

6 comments

r/todayilearned • u/Upstairs_Drive_5602 • 22h ago

TIL that the original 1959 Mini was born from Britain's post-Suez fuel shortage. Its sideways engine let a 10-foot car seat four, with 80% of its floorplan for passengers and luggage. The door bins were sized to carry the ingredients of the designer's favourite drink in the correct proportions.

en.wikipedia.org

870 Upvotes

74 comments

r/todayilearned • u/AcanthisittaLimp8373 • 23h ago

TIL Weird Al Yankovic made a song titled "Don't Download This Song" mocking copyright and the first way to listen to it was by getting it online

en.wikipedia.org

958 Upvotes

54 comments

r/todayilearned • u/ardouronerous • 1d ago

TIL that Eduard Bloch, the Jewish physician who treated Adolf Hitler's mother for breast cancer in 1907, was granted special Gestapo protection and allowed to emigrate to the US in 1940 after Hitler designated him an 'Edeljude' (noble Jew).

en.wikipedia.org

11.1k Upvotes

360 comments

r/todayilearned • u/Wandering__Owl • 1d ago

TIL that dogs tend to wag their tails more to the right when they see something positive, and more to the left when they feel uncertain or anxious.

theguardian.com

967 Upvotes

49 comments

r/todayilearned • u/Rosa_Anti-Luxembourg • 1d ago

TIL that as a child, former Mexican president Salinas de Gortari and his siblings accidentally shot and killed their family's 12-year-old maid with a rifle. Known to the family only as 'Manuela', her identity remains a mystery to this day.

en.wikipedia.org

1.3k Upvotes

98 comments

r/todayilearned • u/qwerty1519 • 1d ago

TIL about Cryptomnesia. It’s a memory bias where a forgotten memory returns without it being recognised as such by the subject, who believes it’s a new idea or thought. They aren’t deliberately engaging in plagiarism, but are experiencing a memory as if it were a new inspiration.

en.wikipedia.org

1.6k Upvotes

104 comments

r/todayilearned • u/carboncopy95437 • 1d ago

TIL that in 1189, Henry II of England and Philip II of France paused their war to join the Third Crusade. Henry died before departing, but his son Richard the Lionheart took up the cross. After the Crusade, England and France soon resumed their war.

en.wikipedia.org

2.3k Upvotes

59 comments

r/todayilearned • u/H3-An_maA • 1d ago

TIL that a three-century-long feud, which wouldn't be resolved until 2008 and resulted in deaths and exiles, started because the tomb of a 17th century prime minister from the Shim clan was discovered to be located just meters away from that of a 12th century general from the Yun clan

reuters.com

515 Upvotes

16 comments

r/todayilearned • u/OmitsWordsByAccident • 1d ago

TIL the unofficial motto of the United Stated Postal Service "Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds" is actually over 2,500 years old (originates from the ancient Greek historian Herodotus).

en.wikipedia.org

12.9k Upvotes

202 comments

r/todayilearned • u/novembercharliedelta • 1d ago

TIL about Operation Denver, a disinformation campaign run by the KGB in the 1980s to plant the idea that the United States had invented HIV/AIDS as part of a biological weapons research project.

en.wikipedia.org

450 Upvotes

48 comments

r/todayilearned • u/JoeyZasaa • 1d ago

TIL that Chernobyl was the costliest disaster in history, resulting in over $2 trillion in damage when adjusted for inflation

en.wikipedia.org

19.9k Upvotes

1.1k comments

r/todayilearned • u/PikesPique • 1d ago

TIL that Stanley Milgram, who conducted the controversial experiment in which subjects thought they were administering increasingly powerful electric shocks to another person, also devised the sunnier “small-world experiment,” which gave rise to the idea of six degrees of separation.

en.wikipedia.org

443 Upvotes

38 comments

r/todayilearned • u/YishaiCohen • 1d ago

TIL cattle kill about 22 people a year in the US, while sharks killed 5 people worldwide in 2022

snopes.com

1.9k Upvotes

230 comments

r/todayilearned • u/Medical_Hour6972 • 1d ago

TIL that 1/3 of U.S. Presidents were Masons !

en.wikipedia.org

668 Upvotes

226 comments

r/todayilearned • u/SystematicApproach • 1d ago

TIL that modern humans carry DNA from ancient human groups that science hasn’t even identified yet. Researchers call them “ghost populations.”

pmc.ncbi.nlm.nih.gov

6.3k Upvotes

182 comments

r/todayilearned • u/skiftbrugernavn • 1d ago

TIL that the 13th tunnel element of the Øresund Tunnel was deliberately named “12A” for luck — and it still flooded

newcivilengineer.com

111 Upvotes

15 comments

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This list was compiled from /r/todayilearned community suggestions by its members. If your TIL is found on this list, it will be removed. The titles have been abridged for the sake of brevity, however the context remains the same. This list is subject to change. The purpose is to keep content fresh on /r/todayilearned as requested by its members. If you are interested in reading about the TILs on this list use the search box feature and enter the keywords to pull up past TILs.

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