Measuring Tools

A measuring instrument is a device for measuring a physical quantity. In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events.

Established standard objects and events are used as units, and the measurement process gives a number for the unit under study and the unit of measurement referred to. Measuring instruments and formal test methods that determine the use of the instrument are the means by which these numerical relationships are obtained.