Everyone now has a smart phone - and usually some smart gadgets at home, that all have the correct time. That did not used to be the case. Less that 10 years ago, time was mainly a product of a person setting some device - a watch, the alarm clock (famously the VCR, which flashed 12:00 after every blackout). But now, we all have smart phones that set our clocks to the same EXACT time.
When you think of it, this is a GIANT change in coordinating the world.
We used to have clocks, and some people famously set them 15 minutes early so they wouldn't be late. And, when you were late, you could look at your wrist, shake it and say, "My watch must be wrong." We all knew it was a lie, but everyone pretended anyway. Now, you can't do that.
And even more amazing when you think of 10,000 years of human history, we only had time zones starting less than 140 years ago! Times zones were invented in 1883 so that we could all agree on the time so trains could run. Before that, time was set whenever the town bell-tower rang out. And they were usually set to local noon.
|Train Time Zone map.|
Weird to think about, right?