Ease-in
This keyword will start slow and speed up to normal by the middle.
Ease
This keyword will start slow, speeding up to fast in the middle, and then slowing back down to the end. This is the default value for this property.
Linear
The speed for this transition will remain consistent throughout.
Ease-out
This keyword will start normal and slow down toward the end.
Ease-in-out
This keyword starts and ends slow, but only hits normal speed in the middle.
Normal
This is the default value. The animation will play forward as expected.
Reverse
The animation will play its steps working backward from last to first.
Atlernate
As long as the animation plays more than once, the direction will keep switching between forward and backward.