This Track is Legacy. Only use this if you are still working with legacy-based Animation Clips.
The Animation Track works very closely with animation clips of the legacy Unity animation system. Each Animation Track represents a different animation layer, along with its blend mode and transform mixing group (the bones it affects). Animations played on tracks on the top, are actually played on top of animations played on the tracks below!
The Animation Track has the following settings:
Animations can be trimmed or looped, and have blend in/out properties to control the transitions in and out of the animation clip and between others.