Length is the distance covered by a straight line segment connecting two points. An object's length is how long the object is - but in the physical sciences and engineering, the word length is in some contexts used synonymously with "distance". The standart unit of length is meter (m).The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second. Height is vertical distance. Width (or breadth) is a lateral distance. Length is usually measured with a ruler or similar device.

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