# What is distance?

• (noun): A distant region.
Example: "I could see it in the distance"

## Distance

Distance is a numerical description of how far apart objects are. In physics or everyday discussion, distance may refer to a physical length, or an estimation based on other criteria (e.g. "two counties over"). In mathematics, a distance function or metric is a generalization of the concept of physical distance. A metric is a function that behaves according to a specific set of rules, and provides a concrete way of describing what it means for elements of some space to be "close to" or "far away from" each other. In most cases, "distance from A to B" is interchangeable with "distance between B and A".

### Some articles on distance:

Field Of View - Machine Vision
... lens focal length sets up the fixed relationship between the field of view and the working distance ... Working distance is the distance between the back of the lens and the target object ...
... of the radar return signal is proportional to the inverse fourth-power of the distance ... an object appears on the sky, but cannot measure the distance accurately at all ... Radar, on the other hand, directly measures the distance to the object (and how fast it is changing) ...
Distance - Other "distances"
... E-statistics, or energy statistics, are functions of distances between statistical observations ... Mahalanobis distance is used in statistics ... Hamming distance and Lee distance are used in coding theory ...
Track And Field - Events - Running - Middle Distance
... Further information Middle distance track event The most common middle distance track events are the 800 metres, 1500 metres and mile run, although the 3000 ... The 880 yard run, or half mile, was the forebear of the 800 m distance and it has its roots in competitions in the United Kingdom in the 1830s ... Physiologically, these middle distance events demand that athletes have good aerobic and anaerobic energy producing systems, and also that they have strong speed endurance ...

### More definitions of "distance":

• (noun): A remote point in time.
Example: "If that happens it will be at some distance in the future"; "at a distance of ten years he had forgotten many of the details"
• (verb): Keep at a distance.
Example: "We have to distance ourselves from these events in order to continue living"
• (noun): Indifference by personal withdrawal.
Example: "Emotional distance"
Synonyms: aloofness
• (noun): The property created by the space between two objects or points.
• (noun): The interval between two times.
Example: "The distance from birth to death"
Synonyms: space
• (noun): Size of the gap between two places.
Example: "The distance from New York to Chicago"
Synonyms: length

### Famous quotes containing the word distance:

Honor the spirits, but keep your distance from them.
—Chinese proverb.

Confucian Analects.

The mystery of the evening-star brilliant in silence and distance between the downward-surging plunge of the sun and the vast, hollow seething of inpouring night. The magnificence of the watchful morning-star, that watches between the night and the day, the gleaming clue to the two opposites.
—D.H. (David Herbert)

Midway the lake we took on board two manly-looking middle-aged men.... I talked with one of them, telling him that I had come all this distance partly to see where the white pine, the Eastern stuff of which our houses are built, grew, but that on this and a previous excursion into another part of Maine I had found it a scarce tree; and I asked him where I must look for it. With a smile, he answered that he could hardly tell me.
Henry David Thoreau (1817–1862)