Why is Newton’s First Law also sometimes called the Law of Inertia?

Question

anonymous · Answer

well, inertia is actually is a resistance to any object which is in motion like air. so that its resistance can change the motion or direction or any other crap of that moving thing..

in same manner , this guy newtons also told that any object which is in motion will in motion will be in motion until any resistance is applied like air, and named it as first law... so , these both laws include change in state of an motive object due to external forces.. so though they became siblings by same father but different mothers...

anonymous · Answer

Because motion (momentum) will not change unless an external force is applied.