Parts of the world have different time zones, you can send a message to that person via social media in which the time stamp says 21:30 at night from your perspective, but when they receive it their clock says 04:30 in the morning -17h in the past despite hanging out via discord chat. They haven’t responded yet until 09:00 (CDT) on Fri which is 02:00 (JST) on Sat, you are already ZZZ so the conversation already ended before it started.

I’m planning to create a group chat with my friends in the future but most of us live in different regions. So, how can response time be in sync despite being positioned in different regions? Will GMT have to be the standard: like “Chat is active between 08:00-22:00 GMT” meaning people will have to work out -/+ hours in correspondence to their time zone whether they are -6 or +12 hours from GMT to stay online in sync.

Even if multiple people are online at the same time: why is time inconsistent (the sun is up in one place while it’s dark in another), you can ask friends what time it is in where they live (internationally) but receive different responses based on their surroundings. This person states it’s 08:00 while you reply it’s 23:00 on the same day with one difference: they’re starting the day while you’re about to finish it moving to another.

  • TheFogan@programming.dev
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    30 minutes ago

    There’s lots, but just like everything, very few people actually can stick with and use them. Probably the thing that I think would be a logical feature in most chat programs, would be if say you put in your timezone into the client somewhere, then when you type a time you put some character before it like *3:30pm - the chat client could determine your timezone, put it in chat as UTC, and each recieving client could automatically convert it to their users timezone (and I suppose some kind of tag to make it so people know it is already translated to their timezone).

  • dhork@lemmy.world
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    3 hours ago

    Yes, when you are comparing times across time zones, you can use UTC time. (UTC is essentially a more modern GMT, there are differences but only the nerds care.)

    You will want to use all times in UTC. But be aware that when you do this, any times that are meant to be the same throughout the year will shift one hour due to Summer Time/DST. Not every region does summer time, and the ones that do start and stop at slightly different times. (And Southern Hemisphere countries do it in Northern Hemisphere’s winter.)

    If that’s too inconvenient for you, or most of your users are in your country, an alternative is to explicitly state the chat hours in your local time zone, with the understanding that it will shift a hour vs. UTC twice a year, and anyone outside your country’s summer time rules will just have to deal with it.

  • ten8tp@reddthat.com
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    4 hours ago

    Yes. GMT is UTC (meaning GMT is +0 and synchronized with UTC), therefore if you have to work out what time it is in other time zones, you use UTC. Your application shows the time in your time zone (unless otherwise specified). Responses will also be shown in your time zone.

  • Noctambulist@lemmy.world
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    3 hours ago

    As others have said, using UTC is the most reliable solution to communicating times across time zones. Everyone only needs to know their own offset (which might change twice a year if their location uses DST). A handy way to mark times as UTC is to attach a “Z” as in 20:00Z, which is part of the international standard covering dates and times ISO 8601.

  • pro_user@lemmy.world
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    4 hours ago

    There is Swatch Internet Time (.beat), which was invented to:

    … simplify the way people in different time zones communicate about time, mostly by eliminating time zones altogether. It also does away with the division of the day into 12 or 24 parts (hours), then 60 parts (minutes), then 60 parts (seconds), then 1000 parts (milliseconds). Furthermore, there is no confusion between the AM/PM system and 24-hour time.

    For example:

    Internet time clock

    • ViatorOmnium@piefed.social
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      3 hours ago

      GMT is always +0, it literally means Greenwich Meridian Mean Time, and the Greenwich meridian doesn’t move just because the UK has summer time.

      • dhork@lemmy.world
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        3 hours ago

        Um ackshually, it’s Greenwich Mean Time, and back in the day it aligned with the average time in the day at which the sun was directly overhead in Greenwich at noon, after taking into account the Equation of Time. (Now it’s just UTC+0).