If scientists had sacred objects, this would be one of them: a single, closely guarded 137-year-old cylinder of metal, housed in a vault outside of Paris. It is a prototype that precisely defines a ...

Nick van Remortel demystifies natural unit systems — and advises what to do when you see a mass expressed in GeV. Several unit systems for describing the natural world exist. The International System ...

In prehistoric times, not much needed to be measured. You ate what you found and lived where you could. The advent of agriculture and civilization, however, necessitated a way for people to measure ...

Wondering why the United States measures things in inches and pounds? The answer will definitely surprise you All countries use the metric system to varying degrees. Most of the world has adopted the ...

The NIST-4 Kibble balance, an electromagnetic weighing machine that is used to measure Planck's constant, and in turn, redefine the kilogram. Jennifer Lauren Lee / NIST Locked in a vault that requires ...

What unit of measurement should be used for specific reports? Whether printing out a check register or calculating square footage, using the correct team is essential. A size mistake can lead to ...