Y-axis is a coordinate system established with geodetic datum as the origin, which indicates the location and occupation of buildings.
Coordinate system is a common auxiliary method in science, such as linear coordinate system and plane rectangular coordinate system.
There are many kinds of coordinate systems, such as Cartesian coordinate system, plane polar coordinate system, cylindrical coordinate system (or cylindrical coordinate system) and spherical coordinate system (or spherical coordinate system). The coordinate system commonly used in middle school physics is rectangular coordinate system, or orthogonal coordinate system.
Broadly speaking, all abstract concepts of things exist with reference to the coordinate system to which they belong, and the same thing will be represented by different abstract concepts in different coordinate systems. The number of related abstract concepts expressed in the coordinate system, that is, the number of coordinate axes, is the dimension of the space where things are located.
Two things that can change each other must be in the same coordinate system.