How are the animation tracks formed

How are animation tracks created?
Is it some sort of interpolation between CFrames/KeyFrames?
The reason why I ask is because I want to be able to

  1. Track say a collision within an animation. An example would be, a player performs a sword slice and collides with a wall.
  2. I want to smoothly transition into another animation. So at a certain point, the player collides with an object, and somehow be able to smoothly transition into some recoil animation. The problem is that I won’t know what time within the first animation track the player will collide into a wall. I can use a touchevent, but the recoil should differentiate depending on the point of the first animation it collided. If I just use the same recoil animation, it could look abrupt and unclean. Is there a way I can create my own track or custom animate it to look cleaner? I want the transition to be fairly precise.