[rhn_mk1]

Yes, but actually no. Precision becomes important once you start digging in. Calculate the GPS time dilation without sufficient precision and you'll be in trouble. Go down to quantum physics to discover that the exact ratio of mass between the electron and proton might matter for your nuclear reactor.

[worksonmine]

You don't even need to get that specific, even web developers encounter this sooner or later, often as a UI bug in what should be really simple math. Then one day you wonder "what the fuck are all these zeroes? Oooooh..."

That's how I learned about it years ago.