Easing | Animation Principles 

A lot of poor animation is a consequence of non-existent easing.
Everything's stiff and linear.
It's in learning to implement some easing that we can make our stuff look a bit more lively.
Because nothing with any soul moves without it.
We speed up, slow down.
Accellarate, deaccelarate.
Yadadada.
The only thing that moves in a calculated and linear way is robots, which, unless you're animating robots, is not how you want things to look.
/ nootall_