Motion is relative to your frame of reference which you can choose arbitrarily.
Most people use the surface of the earth as their frame of reference or their own body depending on the calcualtion they are doing. However, that makes describing the orbits of the planets more difficult so the sun is often used as the frame of reference in that case. If I'm inside a car my frame of reference might be my head, the car or I could choose a spot along the road (the surface of the earth).
From a science standpoint you should get the same answer no matter what frame of reference you arbitrarily choose but it often turns out that choosing a particular frame of reference makes certain calculations much easier.
Just keep in mind that motion is always relative to something and you get to pick whatever that something is when you are solving a problem or doing a calculation. Just don't change frames of reference in the middle of a problem or your answer will likely be incorrect.
relative motion is predominantly horizontal (fault)
all motion is relative to something
In essence, all motion is relative to something. In genereal, motion is relative to the earth, but it depends on what context you are looking for.
Motion is relative to an observer's frame of Reference.
Relative motion is the concept that the motion of all objects is relative to other objects. If you are sitting still right now you are not moving relative to the earth, however you are moving relative to sun.
motion is realtive
At rest and in motion are relative terms. When we say 'in motion' or 'at rest' we mean relative to something else. If you were travelling in a car for instance, you would be at rest relative to the car but in motion relative to the outside world.
Relative to the car road and sun you are in motion.
motion is movement relative to another frame of reference ie snooker ball relative to table moon relative to earth
Comparing one motion to another.
An object's motion in relation to something else