Why did the CIA secretly buy Soviet metal to build the very plane designed to spy on them? How does a metal named after Greek Titans manage to fuse physically with living human bone? If titanium is the ninth-most abundant element on Earth, why is it still so expensive to produce? And how did common chlorinated tap water nearly destroy the manufacturing of the world’s fastest titanium jet? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: mattau93, bigaddam, barath_s, icowboy, justscottaustin, 1fresco, qininator and cheapseats91 To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

Why do people in the UK typically say Happy Christmas while in America it is most commonly Merry Christmas? What made red and green Christmas colors? Is it true that Coca-Cola popularized the modern look of Santa Claus? Why do most of our "traditional" Christmas songs, images and TV/movies come from the 1940s to the 1960s? Brian Earl from the Christmas Past podcast joins us to ELI5 a range of Xmas questions. ... and we explain like i'm five! Help more people fund us by leaving a rating on iTunes. Thank you to Brian Earl from the Christmas Past podcast. If you'd like to hear more excellent xmas episodes, check out Brian's podcast here: https://christmaspast.media/ To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

Why do people in the UK typically say Happy Christmas while in America it is most commonly Merry Christmas? What made red and green Christmas colors? Is it true that Coca-Cola popularized the modern look of Santa Claus? Why do most of our "traditional" Christmas songs, images and TV/movies come from the 1940s to the 1960s? Brian Earl from the Christmas Past podcast joins us to ELI5 a range of Xmas questions. ... and we explain like i'm five! Help more people fund us by leaving a rating on iTunes. Thank you to Brian Earl from the Christmas Past podcast. If you'd like to hear more excellent xmas episodes, check out Brian's podcast here: https://christmaspast.media/ To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

What makes a pearl so mesmerizing, and what is it really? What exactly is a pearl made of, and how does it form inside a mollusk? Can a grain of sand truly cause a perfect pearl? What's the difference between a natural pearl and the cultured ones we see today? How do pearls get their stunning array of colors, from soft pinks to deep blacks? What makes certain pearls incredibly valuable, fetching millions? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: emoposer, iamkunii, cooldrummer1208, Albres, discordant_rhyme, xentonian, enzio901, n19h7m4r3 To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

If every major country is in billions of debt, where are they borrowing from? Who exactly do they owe? Are there any consequences for them being in debt? Why is it a problem when it gets large? Why was Greece in trouble, while Japan seemingly has high debt but is fine?   ... We explain like i'm five!   Help more people fund us by leaving a rating on iTunes.   Thank you to the r/explainlikeimfive community, and specifically the following reddit users whose questions and responses formed the basis of this conversation: emils5, poomanshu, potato_octopi, cop-disliker69, reshkayden, agoraiosbum, cheesewithwhine, aythekay & anjabe96 To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

Did you know bubble gum is traditionally pink simply because the inventor ran out of every other color? Did McDonald’s really try to help kids eat healthier by inventing bubble gum-flavored broccoli? What actually sets bubble gum apart from regular chewing gum? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: dart_catcher, shaka_sulu, bluehellebore, tato7069, ted_normal and charlzpatton To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

What sparked the invention of Morse code, and how did personal tragedy influence Samuel Morse's creation? Is Morse code still used today? How does Morse code rely on timing, and what role do dits and dahs play in understanding messages? Why do some people still feel a connection to Morse code today despite advances in communication technology? How did WWII utilize Morse code for encrypted communications, and what were the implications for message security? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: stanitor, appropriate_trader, effective-ad-6460, twin_spoons, scotterson34, idealblueman, hipp013, beachedwhale1945. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

What makes marble feel cold to the touch, especially in winter apartments? How does the use of marble in art reflect the cultural values of the civilizations that employed it? What exactly is marble and how is it formed geologically? What role does marble play in ancient Greek architecture, specifically in the Acropolis and its iconic structures? How does the history of marble reveal about human ambition, creativity, and the pursuit of perfection? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: reynardb, razeus, pierre_poutine90, forkwhilef0rk, sgrams04, stevewmn, rundna, thaddeusjp. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

Why do modern carriers feature an angled flight deck instead of a straight full-length runway like their WWII predecessors? How fast does an aircraft have to go to take off from a carrier? Why don't planes just fall off the front of the ship when they take off? What are the costs and challenges associated with building longer runways on aircraft carriers? What advantages do nuclear-powered aircraft carriers have over conventional ones in terms of operational efficiency?  ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: hyndis, green_meklar, kal_vas_flam, infernalism, pedopaul, aquatic_mammal, amatulic, generallyawfulhuman. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

Is the Iron in our body different from the Iron used in construction? How did ancient cultures use meteoric iron without knowledge of metallurgy? What makes iron such a vital natural resource throughout human history? Why doesn’t iron in our blood react strongly to MRI machines? How does the imaginative concept of ""space swords"" link history and modern mythology around iron? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: azhiker00, 18_usc_47, dependent_warning_51, lallo-the-long, boredcop, gnonthgol, gailynstarfire, 1strategist1. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

Why do we still change clocks to Daylight Savings Time when so many people dislike it? Who came up with the idea in the first place? Why is there a movement to permanent Daylight Savings Time? Are farmers for or against Daylight Savings Time? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: sushiandwow, eigenfood, tripshed, bunchoatoms, jiceman and grizzletron. To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

If nuclear submarines can generate their own water and oxygen underwater, why do they need to surface at all? Why are submarine propellers always at the back, while airplane propellers are usually at the front? How did submarines and the US Navy play a part in the discovery of the Titanic? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: ilearnrussian, lokiorin, slobbie, hemingwavy, yancy_farnesworth, luckbot, omnipotentsandwich, r3dm0nk. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

What is the gold standard and how did it influence currency value historically? How did the transition from a gold standard to fiat currency shape modern economics? What led to the abolition of the gold standard in the US during the Great Depression? What impact did Executive Order 6102 have on private gold ownership in 1933? How does the US dollar derive its value without being tied to gold? What part did Isaac Newton play in helping gold become the standard precious metal of choice? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: ilearnrussian, lokiorin, slobbie, hemingwavy, yancy_farnesworth, luckbot, omnipotentsandwich, r3dm0nk. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

Did you know a standard lock might have thousands of combination possibilities, yet yours might open someone else's door? How does a master key work such that it can open multiple locks without compromising security entirely? What makes lockpicking more of an art than a science, requiring skill and a deep understanding of how locks function? How can a particular ""jiggle-and-twist"" method sometimes allow a key to open unintended locks successfully? What surprising connections do locks and keys have with human ingenuity and security throughout history? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: QvttrO, TehWildMan_, DJpng, thephantom1492, Childofglass, Jack_Chronicle, Git_Off_Me_Lawn, woofle07. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

Did you know that the original Monopoly board was circular as well as made from cloth? How have Monopoly games evolved over the years to create more engaging experiences for players? Can Monopoly actually reflect the negative impact of monopolies in the real world, rather than just an enjoyable pastime? What are some of the most interesting versions of Monopoly? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: mrpillowthegreat, amisspelledword, jakash, esploratore, nowhereweare, tscrandall, thr33beggars and rorynne. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

What inspired George Ferris to create the first Ferris wheel at the Chicago World’s Fair in 1893? How tall was the original Ferris wheel, and what impressive structure did it aim to surpass? What unique challenges did engineers face to build the Ferris wheel, and how did they ensure its safety? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: jake1oo6, rhomboidus, ez_does_it, demderdemden, thrashingmadness, iammagnuslol, black_magic_m-66 and 1poongoon3. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

What exactly are desiccants, and why are they commonly used in packaging? How does silica gel effectively trap moisture in humid environments? Can you explain the nanoporous structure of silica gel that makes it so efficient? Why do some silica gel packets change color when they reach capacity? Is silica gel really safe to use? Can you reuse them? ... we explain like I'm five. Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: Em_Adespoton, DiamondIceNS, intchd, Gnonthgol, Bosstiality, LCIronmanX, Mr_Automatic, stugautz. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

How does sleepwalking work exactly? Are certain people more prone to it? What types of activities can sleepwalkers get up to? Are there specific triggers that cause sleepwalking? Is it true that waking a sleepwalker can be dangerous? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: lindsey1151, xsnr, happycapsule, bandito21dema and reshkayden To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

How did Poker evolve into a cultural phenomenon beyond just a card game? What makes poker different from other casino games in terms of player competition and strategy? Can you explain the betting process in poker and how players make decisions during each round? Poker on TV often shows those probabilities of a winning hand. How do players calculate this when they're playing? Are there some standard probabilities we should know about? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: TheAireon, stanitor, puck1996, disillusionedJack, AaronSarm, NutellaPatella, Habanero_Eyeball, and lookawake. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com

What makes washing machines such a vital household invention in the modern world? How did washing machines transform household chores from 8-12 hours to a fraction of that time? Could you explain the role of water temperature in washing effectiveness and fabric care? Why do some fabrics, like suits, require special cleaning methods instead of traditional washing machine cycles?  ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: peteymcpetey, trutheality, flashwastaken, draftstone, caliph_ate, silverbolt2000, danielfaa, unique_username1. To the community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: ELI5ThePodcast@gmail.com