Boxing the compass
The points of the compass, specifically on the compass rose, mark divisions of a compass; such divisions may be referred to as "winds" or "directions". A compass point allows reference to a specific heading (or course or azimuth) in a general or colloquial fashion, without having to compute or remember degrees.
A compass is primarily divided into the four cardinal points — north, south, east, and west. These are often further subdivided by the addition of the four intercardinal (or ordinal) directions — northeast (NE) between north and east, southeast (SE), southwest (SW), and northwest (NW) - to indicate the eight principal winds. In meteorological usage, further intermediate points between cardinal and ordinal points, such as north-northeast (NNE) between north and northeast, are added to give the sixteen points of a wind compass. At the most complete division in European tradition, are the full thirty-two points of the mariner's compass, which adds points such as north by east (NbE) between north and north-northeast, and northeast by north (NEbN) between north-northeast and northeast.
Although the European nautical tradition retained the term "one point" to describe 1⁄32 of a circle (in such phrases as "two points to starboard"), by the middle of the eighteenth century, the 32-point system was further extended with half- and quarter-points to allow 128 directions to be differentiated. For most applications, the fractional points have been superseded by degrees measured clockwise from North.
In ancient China 24 points of the compass were used, measuring fifteen degrees between points.
The names of the compass directions follow the 32-point wind compass rose follow these rules:
All of the above named points plus the sixteen quarter winds listed in the next paragraph define the 32 points of the wind compass rose.
The name of a quarter-wind is "X by Y", where X is a principal wind and Y is a cardinal wind. As a mnemonic device, it is useful to think of "X by Y" as a shortcut for the phrase "one quarter wind from X towards Y", where a "quarter" is 11 1⁄4°, X is the nearest principal wind, and Y the next (more distant) cardinal wind. So "northeast by east" means "one quarter from NE towards E", "southwest by south" means "one quarter from SW towards S". The eight principal winds, eight half-winds and sixteen quarter winds together yield a 32-wind compass rose, with each compass direction point at 11 1⁄4° angle from the next. In the mariner's exercise of boxing the compass, all thirty-two points of the compass are named in clockwise order.
...
Wikipedia