2 Animation Principles

Timing
Timing will be quicker or slower depending on the number of frames between given action. Correct timing means objects appear to follow laws of physics. Timing is crucial to establish a character's mood, emotion, and reaction. and how objects should react to force like a push. 


Arcs
Natural action tends happen along an arched trajectory, In animations that follow this principle action will follow along implied "arcs" this creates a more realistic effect. Natural movement such as the movement of a limb should follow an arced trajectory minus mechanical movement, which typically moves across liner lines. An object in motion which doesn’t adhere to a natural arc will appear erratic rather than fluid. when animating you should understand all poses between the two extreme poses, limbs that extend past a logical arc don’t look natural. As momentum increases, arcs flatten out in moving ahead and broaden in turns. 

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