Ruler

This article is about the measuring device-the ruler. For other uses, see Ruler (disambiguation).
"Carpenter's rule" redirects here. For the mathematical unfolding problem, see Carpenter's rule problem.
A variety of rulers
A carpenter's rule
Retractable flexible rule or tape measure
A closeup of a steel ruler
A ruler in combination with a letter scale

A ruler, sometimes called a rule, scale or a line gauge or meter stick, is an instrument used to make length measurements, whereby a length is read from a series of markings called "rules" along an edge of the device.[1] Usually, the instrument is rigid and the edge itself is a straightedge ("ruled straightedge"), which additionally allows one to draw straighter lines.

  1. ^ "ruler noun - Definition, pictures, pronunciation and usage notes - Oxford Advanced Learner's Dictionary at OxfordLearnersDictionaries.com". www.oxfordlearnersdictionaries.com. Archived from the original on 25 October 2017. Retrieved 25 April 2018.