This document discusses key concepts in animation, including keyframes, tweening, onion skinning, frame-by-frame animation, and frame rate. It explains that keyframes define parameters at certain points, tweening generates intermediate frames between keyframes, onion skinning allows viewing multiple frames to aid animation, frame-by-frame animation involves manipulating objects between individually photographed frames to create movement, and frame rate is the frequency at which consecutive images, or frames, are produced. The document also notes that common frame rates are 24-30 fps for video and 12-15 fps for digital animation.