If you could time travel, what would you change ?

Bad idea. Last time someone did this we ended up with this timeline.

The comedy of errors that resulted in World War 1 seems to indicate that there is a group of time travelers trying to make sure this time line happens.
Killing Hans Sprechter

I would go back in time and meet the people who wrote the first ever USB standard. Then I would convince them that all USB connectors have to be reversible from day one so that nobody will ever need to struggle with the 20/80 odds of getting it right on the first try. Come on, it’s two possibilities and the probability of the wrong one is at least 80%. What’s the deal with a connector like that?

Accordingly to the USB inventor, he didn't make it reversible right off the bat because it would need 2x more wires, circuits, and cost 2x more. So you probably [won't be | weren't] able to convince him.
Perhaps a better approach is to tell him that they should be clearly asymmetric, to both touch and sight. Like HDMI connectors are.
tense marking is fun in time travel.
- You can even make the connector look like a B with a larger loop on one side, that when people were like why is it shaped like that you could just say that's the b in the USB
- Paging Dr. Streetmentioner
- You don't need double the wires if you change the recepticle so that you can plug it in both ways, and the recepticle would just have those wires connected on the board.
- tense marking is fun in time travel.
  One of the major problems encountered in time travel is not that of becoming your own father or mother. There is no problem in becoming your own father or mother that a broad-minded and well-adjusted family can't cope with. There is no problem with changing the course of history—the course of history does not change because it all fits together like a jigsaw. All the important changes have happened before the things they were supposed to change and it all sorts itself out in the end.
  The major problem is simply one of grammar, and the main work to consult in this matter is Dr. Dan Streetmentioner's Time Traveler's Handbook of 1001 Tense Formations. It will tell you, for instance, how to describe something that was about to happen to you in the past before you avoided it by time-jumping forward two days in order to avoid it. The event will be descibed differently according to whether you are talking about it from the standpoint of your own natural time, from a time in the further future, or a time in the further past and is futher complicated by the possibility of conducting conversations while you are actually traveling from one time to another with the intention of becoming your own mother or father.
  Most readers get as far as the Future Semiconditionally Modified Subinverted Plagal Past Subjunctive Intentional before giving up; and in fact in later aditions of the book all pages beyond this point have been left blank to save on printing costs.
  The Hitchhiker's Guide to the Galaxy skips lightly over this tangle of academic abstraction, pausing only to note that the term "Future Perfect" has been abandoned since it was discovered not to be.
- Shine rhrough holes going upwards? That's working at least often when it's on a panel...
While you’re there make damn sure they create a coherent naming scheme that allows upgrade paths/versioning.
Sincerely,
USB 3.2 Gen 1×1
USB 3.2 Gen 2×1
USB 3.2 Gen 1×2
USB 3.2 Gen 2×2
- I would go back and introduce semantic versioning in the 60s.

I'd stop the guy who went back in time to stop the first guy from smoking stuff.

Hey hey, edibles are a thing. Ain't gotta damage your lungs to get a buzz..
- True.
  And you could always go back in time to stop me from stopping you from stopping the guy.
  That's why I think time travel will never allow history to be changed, and I think Rick and Morty may have done a bit about that.

Go back to 1911 and convince Taft to concede the Republican nomination to Roosevelt. That allows Roosevelt to stomp Wilson, get the US into the war before Russia left, and get the war over with years earlier.

This prevents both Stalin and Hitler from rising to power, and prevents most of the European theater of WW2, as well as a host of other knock-on effects.

https://youtu.be/hLiI6kXZkZI?si=YJZMmkpOH4FZQiLt

In this scenario Lenin does not manage to take over Russia and the warning to the world by the real life examples of Germany and Italy about the dangers of fashism does not happen either. Authoritarianism raises its ugly head later in a world with better weapons and more destructive potential for humanity.
Would that prevent the space race?
- I doubt it. The Russians are still gonna want to try to beat the US at anything they can, and prove themselves on the global stage, but it may have been a cooperative venture, instead of competitive.

Stop that kid from falling into Harambe’s enclosure by any means necessary.

🫡

I'd go back and convince that art school to accept a certain art student...

I did nazi that one

I'd like to say something noble like warn Amelia Earhart, or hookup Adolph with some Bob Ross videos. But if I'm being honest, I would probably be selfish. I would tell past me to not fuck up quite a few things that past me royally fucked up.

As we learned from the Butterfly Effect, changing the past only results in Ashton Kutcher getting more power.

My net worth.

Think of all the good I could do with a trillion dollars. I'd have to create a lot of destruction of other people's wealth to get there but they will understand. I really need a trillion dollars!
- Got to do it in stages so it doesn't look too premeditated.
  Start a online auction site where people can sell their stuff and you get a small cut of the profit.
  Then to help people on board start a payment processor company to ensure that the sellers ship their goods and that buyers pay.
  Once that has established, go public with it so that your stock sales can support the existence of your current portfolio while you dabble in other things that you know are very profitable.
  Once you have that going, which will take a few years. You can take a victory lap or two and maybe pay some PR firms to make you look like the cool rich kid on the internet that everyone wants to hang out with.
  Then you can do stuff like starting a spaceship company and helping to bring about the end of the internal combustion engine by starting an electric car company and doing some solar panel stuff.
  Eventually you'll be the richest person on the planet and then you can get to doing the really fun stuff assuming you don't like tank all of your personal reputation by blowing 20% of your net worth on a microblogging website or something while disavowing your trans daughter.
  I mean, if you're smart enough to do all the other things surely you wouldn't blow it at the five yard line like that.

I'd have Al Gore win.

Well... He did.
Turns out it didn't matter.

Save the gorilla, save the world

I've a tattoo based on that show
- Nissan Versa?

I would've gone to bed earlier tonight

Warn about how plastic (especially single-use) is a major pollutant, with microplastics managing to get into our organs with long term consequences we are yet to grasp.

It did push our technology and way of living forward, but at what cost?

You'd be the crazy manbearpig dude. Nobody would listen to you. How would anyone be able to persuade the people?
That wouldn't work because you're a single person fighting against the same companies that finance climate change denialism. Hell, between understanding that leaded gasoline was harmful and banning it were at least 20 years
- Yeah but the OP question isn't asking what you would do, but rather what you'd change. If the question was about what people would do, half these answers have a lot of explaining to do.

I would make sure my parents never met.

But then you couldn't go back and make sure they never met
- So are they saying they're trying to crash this simulation once and for all??

i would not eat the kiosk chili dogs i ate earlier—they were pretty fucking bad.

Instead you got the hot pockets and are now on the toilet.
- I would accept that trade.

I'd go hunt down Ronald Regan at about age 30 and empty an entire magazine of .45s into his dome while he slept.

Oooooh I like this one! Please do humanity the favor!
Was looking for Regan.

I'd go back and write a book with just enough truths to cement myself as a soothsayer. I'd then warn of wars, eco disasters, pandemics, natural disasters. Then I'd invest some money in some good places and make sure it made it to my kids after I'm gone.

I think saving JFK would really alter the timeline. I doubt Nixon would have ever been president.

Preventing the Iranian hostage crisis might also have had a huge impact.

Have your read 11/22/63? It's Stephen King 's take on what would happen if a time traveler tries to stop the JFK assassination.
Great book, in my opinion.

I would try to save the roman republic and prevent the roman kindgom. It would also be interesting to see what would have happend if they never switched to christianity.

But the Roman Republic (509 BC–27 BC) happened after the Roman Kingdom (753 BC–509 BC).
The kingdom was before the republic. I assume you want to prevent the empire?
- yes ofc you are right
To prevent the empire would be more complicated than it looks like, since you got multiple rebellions and civil wars popping up as early as 135 BCE. They ultimately boiled down to
plebeians and/or slaves pissed due to poor living conditions
local peoples rebelling against Roman oppression
some patrician family wanting a larger slice of the pie
And those are all problems that are damn hard to address without leading to plebeians being manipulated, local peoples being suppressed, and cutting down the power of the patricians by a central, strong government. That's basically what Caesar tried to do, and Octavian achieved.

I'd find the first motherfucker that started smoking stuff, whether it was first tobacco or whatever, and get rid of him/her before anyone else ever learned of the practice/habit.

Would have been better health for countless people afterwards, if simply nobody ever knew..

Eliminate tobacco smokers? US Govt. tried, however American Indians are still with us today.
- No, eliminate the single individual that originally invented tobacco smoking. Then nobody from that point on would ever know and the problem would have never existed in the first place.
  Nip the problem directly at the source ya know. Guess you're not all that good with these sort of hypothetical time travel thoughts..
Smoking was discovered independently in many cultures with different substances used by different cultures. In the Americas, it was tobacco, while the Scythians of Central Asia used cannabis in ritualistic hotboxes, as evidenced by archaeological finds of smoking tools in kurgans. Other regions, like India and Southeast Asia, saw the smoking of opium and herbs.

I would try to prevent the Holocaust from happening.

I'd add the Spanish Inquisition to that agenda. But who knows, perhaps the Holocaust might not have ever happened if the Spanish Inquisition never happened. 🤷‍♂️
Time travel thoughts bring up all sorts of hypotheticals...
- There are many ways to stop or deeply alter the Spanish Inquisition, like never getting christianity going, never getting islam going, ensuring the Arabs wipe out all the christian kingdoms of Andalusia, ensuring the Cordoba Caliphate doesn't disintegrate, doing something to both Isabella I of Castille and Ferdinand II of Aragon so they don't get into power.
- Might be worth it to sink the Nina the pinta and the Santa Maria Midway across the Atlantic.
  If Columbus never made it back to Europe that would have delayed expansionism a good while.
  If I could also somehow go to the Americas and provide some interesting artillery to the Eastern coastal tribes that would probably help even more.

I would prevent Lewis Powell from authoring the document that outlined how to capture the courts and put us under the control of unelected judges.

There would be a rather catastrophic malfunction of a certain golden escalator in 2015.

A lot of things I didn't mean to, most likely.

I prefer to rewind time with me along, be young again, that kind of time travel. Of course with my knowledge and memories of up to before my "time travel", be retained. I could only remember what I could any way. The future would surely not happen exactly as the same before. Live a new younger life, a seemingly fresh restart at an early point in my life.

I'd invent the printing press during the classical era and watch what happens from there. I guess the folks at Carthage would also enjoy knowing about paper making, better wind-powered sails for ships and to be on the lookout for those "Romanes"

Well that first guy smoking stuff will have enough to deal with so probably something else.

I guess I would try to warn people that the tsunami was coming.

Everyone treated you like a loony idiot before the tsunami, and now you are in a NSA basement getting tortured for "future information".

i would find the first guy that started smoking stuff and congratulate them for inventing fire

After the bitcoin shortage oroviked by a by of 1.000.000 coins, its already low value plummeted and all the crypto bros started to use bitcoin2 instead effectively killing off the original bitcoin.

Get rid of Ronald Reagan.

Nothing just incase.

I would try to match Genghis Khan up with a proper dad.

That first guy smoking stuff is gonna get rekt

IMO everyone has the right to live a healthy and happy life

Depends on time travel method and how would it affect reality (would it create a new timeline or replace the one we currently live in?).

time to kick that fish back into the water where it belonged. Stay in your lane, ancient precursor animals.

+273 EXP
Level Up!!
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I would get a bunch of party hats in RuneScape.

Ah, the good old days when having a phat was a mega status symbol. And seeing a Christmas cracker was mindblowing.

Maybe go back in time and punch my dad in the balls about 9 months before I was born.

Then all that would remain of me would be a weird story where my dad got socked in the nuts by a ghost that looked just like him.

Only later do you find out your uncle is actually your father because of a bizarre incident where your dad got his nuts punched by an unknown person never seen again
- Good theory but my parents were in another country when I was conceived so there is literally no way one of my uncles could have done that.

I'd find the guy who became the first guy to smoke stuff after the original first guy got stopped.

What is this referring to? There's at least 10 posts about smoking stuff - what does this mean? 🤔
- I think everyone is just memeing on the original comment.

Changes could have so many repercussions even well meaning actions could make things worse. The safer bet would be to collect lost books and art.

That said, stopping the Lincoln assassination is tempting. I'd hope to change reconstruction to better wipe out the confederacy, prevent lost cause doctrine, and better integrate former slaves into full citizenship and society.

Bring back Sodium batteries and how to make them as well as solar panel production. Probably to Nikola Tesla.

To be a bit more precise whatever the easiest to produce versions of each are not the best ones so they could actually be produced at the tech level at the time.

I'm sure they would still end up creating equivalents of oil Barons etc. but at least it would be based on a cleaner tech and more able to improve from there.

Have you learned nothing from science fiction stories? I would not change anything.

Well, I don't think anyone is really sure just how exactly time travel can mess with stuff. I would probably take a page from some time travel movie I saw. I would want to avoid any sort of temporal paradox and avoid too many changes.

So, I would probably remove myself from the equation as much as possible. Go to a hotel or somewhere where I can avoid accidentally running into anyone I might know. Leave all electronics behind, but take a book or something. Spend the whole day avoiding TV/News/People and just reading or work on perfecting a skill. At the end of the day I would call up a broker from the hotel room and find out which stock had the greatest percentage gain that day. Just enough information for one good trade.

Then I would go back to that morning, buy up a ton of that stock, live out life normally, then sell the stock at the end of the day.

Rinse and repeat for a short time.

I would absolutely avoid something like winning the lottery, but for those of you who would use time travel to win the lottery, you might want to follow the advice from this comment here: https://old.reddit.com/r/AskReddit/comments/24vo34/whats_the_happiest_5word_sentence_you_could_hear/chb38xf/

I'd tell my younger self to stop fuckin carving "Operator symbols" into furniture. And also to get into playing minecraft...

I would install an automated missile system on every single would be colonizer country's waters, that would sink their ships when they tried to leave port