The Problem with Time & Timezones - Computerphile

30 dec 2013
2 547 126 visningar

A web app that works out how many seconds ago something happened. How hard can coding that be? Tom Scott explains how time twists and turns like a twisty-turny thing. It's not to be trifled with!
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This video was filmed and edited by Sean Riley.
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  • The camerawork makes this so much better

    Ao ArashiAo Arashi14 dagar sedan
  • As front-end developer (kinda full-stack tho xD) I never thought I was gonna have issues with timezones. But here I am, having issue with server and client being in different time zones and I have to deal with "daily" resets... All of this reminded me of this brilliant video.

    Aleksandar DelicAleksandar DelicMånad sedan
  • Tbh we need to abolish timezones

    Sam BehnerSam Behner2 månader sedan
  • Very well done 😂

    PZIKO333PZIKO3332 månader sedan
  • imagine you download a program to calculate some time durations and it asks you whether you support israel or not

    Endoteria 1998Endoteria 19982 månader sedan
  • I'm suddenly a lot more open to living in the present

    Henry JubedaHenry Jubeda4 månader sedan
  • This is the first time I’ve ever felt pity for Tom Scott. Thank you, Mr. Scott for going there before me and giving this warning.

    PrinceAlbertsPrinceAlberts4 månader sedan
  • Oh yeah I'm saving this one

    rocknriffifyrocknriffify5 månader sedan
  • Why do you use England when it’s the uk that changes at those times not just that one of the four nations

    Alan GardnerAlan Gardner5 månader sedan
  • Then you get a call from Arizona saying "Oh we don't do Daylight Savings Time." And then you get a call from the Navajo in Arizona saying "Oh we actually DO do Daylight Savings Time."

    Nicholas HartleNicholas Hartle6 månader sedan
  • Another proof that time isnt real, it's made by humans to "simplify" when to meet.

    chris smookchris smook6 månader sedan
  • I’ve been pronouncing Greenwich wrong my entire life

    Luis FernandezLuis Fernandez6 månader sedan
  • My mom doesn't know with certainty the day of her birth. That is a bit unusual for Germany, where people take pride in recording everything meticulously. The problem is, she was born in the late 1940ies around midnight-ish, in what was then the Soviet-occupied zone of Germany. And the Soviet government decided that in that year, the way DST works should change, and apparently they made a bit of a mess of it. Historical data disagrees on what time exactly the shift did take place. And even if you could nail down the official time, there would be no way to know whether the midwife's watch would be on the old, or on the new date. Thankfully, astrology seems to be the only field where it causes "actual" problems.

    steve1978gersteve1978ger7 månader sedan
  • And I am on +9.5 but speak like you 😄

    Mark WilliamsonMark Williamson7 månader sedan
  • At least we only have one planet to manage. Imagine a multiplanetary civilisation having to deal with this crap

    RandomSlavicGuyRandomSlavicGuy7 månader sedan
  • And THEN another historian calls and says that most countries at the time defined their years relative to the reign of their leaders...

    Svavar KjarrvalSvavar Kjarrval7 månader sedan
  • Then you get a call from the Roman historian, who had 90 extra days added to permanently fix the Roman calendar.

    canismajoriscanismajoris7 månader sedan
  • Tom Scott's facial expressions remind me of my friend's.

    BraydenBrayden7 månader sedan
  • The only thing I took from this was that the year used to start on my birthday

    Ben SmartBen Smart7 månader sedan
  • Pi and 1/e hours

    Waluigi is the king A. SmithWaluigi is the king A. Smith7 månader sedan
  • i think I'm gonna cry

    pixsie stixspixsie stixs7 månader sedan
  • the ammoubt of anger in toms voice when he was talking about the astrophysicist

    Brandon RoughleyBrandon Roughley8 månader sedan
  • damn all this and time isn’t even real

    Ellie AndrewsEllie Andrews8 månader sedan
  • A bit overly dramatic. It's literally UTC implementation and seconds from the Epod in unix takes care of this. And every other operating system is irrelevant, because don't deal with the workload of anything serious anyway so who cares if it's a few seconds or even a few hours off.

    TrasherBinerTrasherBiner8 månader sedan
  • The video brings no useful information whatsoever

    Artem DArtem D8 månader sedan
  • and then special relativity comes along

    GamingboxGamingbox9 månader sedan
  • Financial years have 52 or 53 weeks depending on if the Thursday of the first / last week is is within 7 days of the start of the new year

    Evil WizardEvil Wizard9 månader sedan
  • So not timezones but DST, leapseconds and forced calendar changes or the problem.

    Kris MKris M9 månader sedan
  • Don't forget to ask Einstein, as he may says: Your time is not same as my time.

    Zymic EnomotoZymic Enomoto10 månader sedan
  • I think its 23:59:60

    tomtalk24tomtalk2410 månader sedan
  • The mythical programmer: Ight Imma Head Out

    Xane CosmoXane Cosmo10 månader sedan
  • I seem to get a lot of phone calls

    Fredrik StaffanssonFredrik Staffansson10 månader sedan
  • and my brain got entangled for a leap second now ! :/

    Randomness channelRandomness channel10 månader sedan
  • Say their names. Arthur David Olson, Paul Eggert. Absolute heroes.

    slowgaffleslowgaffle11 månader sedan
  • "So it was two hours ahead of Greenwich despite having Greenwich" LMAO It killed me xD xD xD

    Gwennan EliezerGwennan EliezerÅr sedan
  • yuou know nepal wow

    Sujit TamangSujit TamangÅr sedan
  • As a php developer I can tell you this guy is spot on lol

    Will To WinWill To WinÅr sedan
  • As a developer, It's painful to hear this problem

    Badar WildanieBadar WildanieÅr sedan
  • I'm surprised he managed to make it through this entire video without mentioning Arizona, which does not follow DST, except for the Navajo Nation within it which does, except for the Hopi Nation withing that which doesn't, except for the part of the Navajo Nation that lies inside the Hopi Nation which does.

    a pa pÅr sedan
  • For 5 years on- yeah, we'd totally open up with “G'day, mate”. Source: am Australian :P

    horngeek 91horngeek 91År sedan
  • Been there. It's a nightmare. Great video.

    PhilPhilÅr sedan
  • Forgot to include Morocco's switching back to standard time during Ramadan, then back to DST once Ramadan is over, if it falls during summer. LOL

    Ivy Agnes NguyenIvy Agnes NguyenÅr sedan
  • I will never-ever believe time exists. Prove me wrong.

    1Mateø1MateøÅr sedan
  • Nope nope nope im NEVER dealing with time zones EVER

    sub zerosub zeroÅr sedan
  • Before ireland left the UK we were actually in a different time zone. Also next year the EU is voting against getting rid of changing the hour from summer to winter time so ni and the Republic would have two different times potentially

    eoinh1eoinh1År sedan
  • Ive watched this video 6 times over the last year. Why am i here again?¿?¿

    GhostytytyytbedhhGhostytytyytbedhhÅr sedan
  • Old video, but he forgot to mention that a minute can have up to 62 seconds, not just 61 as mentioned. :D :D :D Also it can co the other way around. Some leap seconds are negative, meaning the minute has just 59 seconds, so it skips from 58 to 00. Well, I think it can be two here too, so from 57 -> 00.

    SkalliSkalliÅr sedan
  • Why not give the users an easy to use UI with rules which enables them to modify their own time however they please?

    imagoimagoÅr sedan
  • Apparently the wizards at Microsoft decided that Power BI, one of the most widespread analytics operation on the planet would only display dates on the web in UTC. It shows your locale when you are building it in Power BI desktop, and the same for the first refresh after publishing on the web, but then reverts to UTC. I hate daylight savings time.

    Nick DewittNick DewittÅr sedan
  • Back in my day, we had to walk to school. Up hill. Both ways. And we had to hustle, 'cuz Greenwich was two hours ahead of Greenwich!

    Kenneth SizerKenneth SizerÅr sedan
  • It's so ironic that how the video has also been published on dec 30 and in one or two days again the time-zones would have changed into the next year XD

    Shantanu PagareShantanu PagareÅr sedan
  • This it's one of my favorite videos ever.

    Stephen BetzStephen BetzÅr sedan
  • So basically, if I call someone in australia, I make a phone call into the future? ok.

    EXcentriXEXcentriXÅr sedan
  • Damn took me 6yrs to reach here😅. Greetings from Nepal!!

    Sudip BishwakarmaSudip BishwakarmaÅr sedan
  • Do you know how many- That's not even funny.

    Steve Urkel from GoosebumpsSteve Urkel from GoosebumpsÅr sedan
  • 6 years later and I still feel his pain.

    Dan PowersDan PowersÅr sedan
  • I thought of the Julian/Gregorian calendar thing early in the video, but I didn't think it would be relevant, since at that time time zones didn't really exist and every city might have had a slightly different time.

    MinecraftMini1009 | Videogame SoundtracksMinecraftMini1009 | Videogame SoundtracksÅr sedan
  • This is the single best video on Computerphile

    Leonardo dos Reis GamaLeonardo dos Reis GamaÅr sedan
  • And then you get a call from Elon Musk in which he wants timezones for Mars

    Name Last NameName Last NameÅr sedan
  • I'm a quality assurance engineer and two collegues from work told me to watch this once I said that the bug we're having should be easy to fix... Never have I been so wrong in my life.

    Alexander the not so greatAlexander the not so greatÅr sedan
  • Use UTC

    BO CHENBO CHENÅr sedan
  • I honestly just had to stop watching this because I was getting stressed out by the time zones.

    Get me 169 subs and I will reveal somethingGet me 169 subs and I will reveal somethingÅr sedan
  • recommended wow

    Miles of MemesMiles of MemesÅr sedan
  • you're forgetting about that earthquake that slowed down the rotation of the earth by 1 millisecond

    Burnt GDBurnt GDÅr sedan
  • Thank you for calling them programmers and not "Software Engineers".

    Kori114Kori114År sedan
  • Yikes. We are currently working on an app just like this. It was hard enough without any exceptions. Can't wait for the calls to start coming in.

    Rob GravelleRob GravelleÅr sedan
  • This is a very general tip for a lot of programming: don't reinvent the wheel. Before you make something, check if someone else made it first.

    MrHatoiMrHatoiÅr sedan
  • Should computer coders simply learn to say NO - bugger off! If people want to be stupid let them do it but don't reinforce the deviant behaviour by producing a work arround!

    Robin WellsRobin WellsÅr sedan
  • This is one of my favorite SEworld videos of all time. I've shown this to so many people, and even the non-computer people find it fascinating and hilarious. Thank you so much for making this video, and others like it.

    Anjili VeachAnjili VeachÅr sedan
  • Time does not exist

    Fedaljon EsenasalFedaljon EsenasalÅr sedan
  • SEworld recommendations sent me here

    Pyro FlarePyro FlareÅr sedan
  • True definition of "Programmers Hell"

    nadenitzanadenitzaÅr sedan
  • Thank you MomentJS

    Rafa FTPRafa FTPÅr sedan
  • Why am I crying?

    Rafa FTPRafa FTPÅr sedan
  • And then you get a call from the ISS where time passes at a different rate because of the different gravitational field strength.

    redjr242redjr242År sedan
  • It actually sounds interesting, coming up with a model abstract enough to accommodate all of these scenarios. How to do it elegantly, WITHOUT using spaghetti code and tons of edge cases?

    Michiel HelvensteijnMichiel HelvensteijnÅr sedan
  • 1:26 I am from Nepal

    Nissan SubediNissan SubediÅr sedan
  • And Thailand is in the year 2562

    Philp menownPhilp menownÅr sedan
  • My absolute favourite Computerphile video. Sorry professor Brailsford!

    PrettyBlueThingsPrettyBlueThingsÅr sedan
  • Here from Nepal

    sagar lamasagar lamaÅr sedan
  • 6:49 me this whole video

    pls sub to mepls sub to meÅr sedan
  • I got a lot of anxiety from this

    decideddecidedÅr sedan
  • An excellent rant! - Love it. Been there. Done that. Haven't been the same since

    Karl JørgensenKarl JørgensenÅr sedan
  • Best rant ever.

    Random PC-UserRandom PC-UserÅr sedan
  • "AND THEN, You get a call from the astrophysicist who says 'by the way, we just had a leap second.' And at this point, you just kind of go 'What.'"

    NoahNoahÅr sedan
  • Im a programmer and i have never encountered this, am i lucky?

    Hammy Boi11Hammy Boi11År sedan
  • man that sounds like a horrible programming task.... let me just use this as a controlled assessment.

    Benn WoodbridgeBenn WoodbridgeÅr sedan
  • Nice

    VaTaNTRVaTaNTRÅr sedan
  • Wait why don’t you just put a dial that says what hour/second it is that the user sets him/herself

    Hopeless ContentHopeless ContentÅr sedan
  • Hey!I am from Nepal..I got surprised and happy to listen the name of my country in your video!!!Thankyou.

    Rimas larahkRimas larahkÅr sedan
  • i've seen this video a dozen of times and i just dont get tired of hearing it.. :D

    TEQ SnukkaTEQ SnukkaÅr sedan
  • what an absolute madlad :D love the video

    vnika55vnika55År sedan
  • Just think how difficult all this time stuff would have been to work out before computers!

    Keldor314Keldor314År sedan
  • 2:39 is exactly what I am doing now.

    Robert VandenbergRobert VandenbergÅr sedan
  • Looks like he was traumatized by time zones.

    Ruslan MasinjilaRuslan MasinjilaÅr sedan
  • i have never cared much for time zones, i have never been in a situation in my life where different time zones has affected me aside from talking to someone on the other side of the world and figuring out when is the best time to contact that person, but this video was presented so well, that it was both informative and entertaining... you just earned a new sub!

    AceAceÅr sedan
  • so 2012 has been miscalculated.....

    ugm ugmugm ugmÅr sedan
  • I really have to pause the video to groan...

    Ikkaru RisanIkkaru RisanÅr sedan
  • And then you get a call from Japan.

    PicoriPiPicoriPiÅr sedan
  • 6:39 this is a broken man

    A JA JÅr sedan