In the spatial rectangular coordinate system, let the thumb of the right hand point to the positive direction of the X axis and the index finger point to the positive direction of the Y axis. If the middle finger can point in the positive direction of the Z axis, this coordinate system is called the right-handed rectangular coordinate system. On the contrary, it is a left-handed rectangular coordinate system.
Spatial rectangular coordinate system: cross the fixed point O and make three mutually perpendicular number axes, all of which take O as the origin and generally have the same length unit. These three axes are called X axis (horizontal axis), Y axis (vertical axis) and Z axis (vertical axis) respectively. Generally called the coordinate axis. Usually, the X-axis and Y-axis are arranged on a horizontal plane, while the Z-axis is a vertical line. Such three coordinate axes form a spatial rectangular coordinate system, and point O is called the coordinate origin.
Baidu encyclopedia-right hand coordinate system