frame of reference(In physics, a frame of reference (or reference frame) may refer to a coordinate system used to represent and measure properties of objects such as their position and orientation. It may also refer to a set of axes used for such representation. Alternatively, in relativity, the phrase can be used to refer to the relationship between a moving observer and the phenomenon or phenomena under observation. In this context, the phrase often becomes "observational frame of reference" (or "observational reference frame"). The context may itself include a coordinate system used to represent the observer and phenomenon or phenomena. WAD Alexander Demidov)
co-ordinate system(A reference system used to measure horizontal and vertical distances on a planimetric map. A coordinate system is usually defined by a map projection, a spheroid of reference, a datum, one or more standard parallels, a central meridian, and possible shifts in the x- and y-directions to locate x, y positions of point, line, and area features. A common coordinate system is used to spatially register geographic data for the same area; Система отсчета, используемая для измерения горизонтальных и вертикальных расстояний на планиметрической карте. Система координат обычно определяется проекцией карты, исходным уровнем, одной или несколькими стандартными параллелями, центральным меридианом, возможными смещениями по направлению осей Х или У для определения координат по осям Х и У точки, линии или отдельных параметров изучаемого участка. Обычная система координат используется для пространственной регистрации географических данных этого участка)
