Length is a measure of one-dimensional space. Usually, when measuring the side length of a straight line in two-dimensional space, the one with a large length value is called long, which is neither greater than its value nor wider than the side length. So width is actually a measure of length, so the height of "vertical length" is measured in three-dimensional space. * * * There are kilometers, kilometers, kilometers, meters, inches, centimeters and millimeters.

Therefore, the length in daily life is the distance of the vertical line segment from one point to another.