How big is a kilobyte?

As best I can tell, there is no broad consensus on how large a kilobyte is. Some say that a kilobyte is 1000 bytes while others say it's 1024 bytes. Others are ambiguous.

This also means that the industry does not agree on the size of megabytes, gigabytes, terabytes, and so on.

Not entirely new information to most of us, I would presume, but in my head canon a kilobyte is 1024 bytes, even though that technically doesn't make any sense from a metric perspective. To make matters worse, as soon as we get into the gigabytes and terabytes, I tend to back to thinking in terms of thousands again since it just makes more sense. The kibibytes and cohorts are a way to properly distance the base 2 system from the base 10 one, but I've never heard anyone in day-to-day speech make that distinctions outside of really nerdy circles.