I always wondered how much exactly a ton is, because people use that term for everything and nobody agrees. It turns out there are three different types depending on where you are:

The short ton used in the United States (2,000 pounds or about 907 kilograms), the long ton from the United Kingdom (2,240 pounds, almost 1,016 kilograms), and the metric ton, which is the global standard with exactly 1,000 kilograms. All of this comes from an old English barrel called a 'tunne' that was used to store wine, so basically they measured how much weight a loaded ship could carry.

The interesting thing is that this causes a lot of confusion in current trade. An American company shipping cargo to Europe has to clarify whether they are talking about short or metric tons, because otherwise it ends up with measurement disasters. That’s why science always uses metric tons to avoid these mix-ups.

In practice, how much a ton is totally depends on the context: mining, construction, shipping, everything is measured in tons. Even carbon emissions are reported in metric tons. And well, when someone says 'I have tons of work,' they obviously aren’t talking about kilos, it just means they have a lot. There’s even a 'ton of refrigeration' that measures the cooling capacity of air conditioners. The point is that understanding the difference between these types helps you avoid serious problems in any business or international transaction.