Standard international units such as second (time), metre (length) and Kelvin (temperature).
A system of standard prefixes are used, e.g. mm is millimetre, ms is milliseconds
T tera 1012 1,000,000,000,000
G giga 109 1,000,000,000
M mega 106 1,000,000
k kilo 103 1,000
m milli 10-3 0.001
μ micro 10-6 0.000,001
n nano 10-9 0.000,000,001
p pico 10-12 0.000,000,000,001
