NIST General
The National Institute of Standards and Technology is a physical sciences laboratory and a non-regulatory agency of the United States Department of Commerce. Its mission is to promote innovation and industrial competitiveness.

Science Facts Written by NIST General
Origins Of The Meter
The origins of the meter go back to at least the 18th century. At that time, there were two competing approaches to the definition of a standard unit of length. Some suggested defining the meter as ... Continue reading

Leaps and Bounds
Leap years are years with 366 days, instead of the usual 365. Leap years are necessary because the actual length of a year is 365.242 days, not 365 days, as commonly stated. Basically, leap years ... Continue reading

How We Use Crystals To Tell Time
Quartz clock operation is based on the piezoelectric property of quartz crystals. If you apply an electric field to the crystal, it changes its shape, and if you squeeze it or bend it, it generates an ... Continue reading
Dress Sizes The Scientific Way
In pre-industrial America, most clothing was crafted at home or by professional tailors or dressmakers from individual measurements taken of each customer. In the early Twentieth Century, the growing ... Continue reading
Unit Of Luminous Intensity (candela)
Originally, each country had its own, and rather poorly reproducible, unit of luminous intensity; it was necessary to wait until 1909 to see a beginning of unification on the international level, when ... Continue reading
