What is a derived unit of measure?

Answer 1

The best-known system of units is the SI, so I'll use it as an example. SI has several "base units", like meter (for length), kilogram (for mass), and seconds (for time) (a total of 7 base units). Other units are derived from the seven base units; for example, areas are measured in meters2, volumes in meters3, speeds and velocities in meters/second, etc.