FLIP is an approach to animations that remaps animating expensive properties, like width, height, left and top to significantly cheaper changes using transforms. It does this by taking two snapshots, one of the element’s First position (F), another of its Last position (L). It then uses a transform to Invert (I) the element’s changes, such that the element appears to still be in the First position. Lastly it Plays (P) the animation forward by removing the transformations applied in the Invert step.