Latency, propagation delay, ping, call it what you will but a digital connection is never as fast as you think.....
With delay times measured in milliseconds and accumulating at every digital transition as well as distance travelled they can all add up to a noticeable delay.
Its usually only when we have a side by side comparison that we notice it, so for example try video calling someone next to you on their phone from yours and you'll quickly notice the time lag. Such delays are also evident when a newscaster hands over to an outside reporter with the latter stood there with a silly smile for a moment before they respond.
With Amateur Radio
you'll sometimes experience a delay before the other station responds because they are relying on an online software defined receiver and I never got on with DMR radio
due to garbled voices with digital compression let alone the annoying delays between transmissions.
You can experience it even with CB radio
if you make a test transmission to your nearest KiwiSDR receiver ( http://rx.linkfanel.net ) and you'll notice the slight delay before you hear your transmission coming back over the internet and through your computer.
In most instances we never notice it as we don't usually make comparisons, so for the example I gave of a video call usually the respondent isn't sitting next to you so each of you will never usually experience it.
Even with the speed of light being as fast as 186,000 miles a second (or almost 300,000 km per second for the metric heads) there is still travelling time associated even with a direct radio
connection and often our DX transmissions are bouncing off the ionosphere so travelling further than we think. (Let alone 'long path' propagation.
Usually however we don't notice or maybe even care with the thrill of the DX contact being more important.
Great video Zolee and thanks for posting. (Got me 'waffling'!
All the best,