A keyframe is a frame on a timeline where something significant occurs. It usually refers to the position of something - like an arm, a finger, a pose, a physical location. However, size, rotation, and all the other aspects can be keyframed. So can changes in the materials or morphs. Keyframes are usually intentionally set, although sometimes people set their software to automatically generate keyframes when they change some aspect of the objects in the scene. In animation, the computer generates the intermediate steps to change objects between keyframes. Ultimately it boils down to the animator saying, "I want this object to be like this (size, position, rotation etc.) right at this point in time. I want it to change to this (size, position, rotation etc.) at another point in time." The specific, desired pose, size etc. would be keyframed at the desired points in time. (Was that too simplistic or too technical?)

Before they made me they broke the mold!
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