How do we measure length, weight, and how much a cup holds?
Steps, Lumps & Cups
How do we measure length, weight, and how much a cup holds?
Here's a strange and wonderful fact: a thing has no idea how big it is. A table doesn't know it's "tall." A bag of apples doesn't feel "heavy." Size and weight only become real when we hold them up against something we already agree on. That something is called a unit — and measuring is just the art of comparing.
Long ago, people measured length with whatever was handy: their own bodies. A "foot" really was about the length of a foot. A "cubit" was elbow to fingertip. It worked fine — until your foot and my foot disagreed, and the whole town argued about how long a rope was.
