The Animation API has its own vocabulary—it may be familiar to the readers who have done some animation work. It also has a few different ways to interact with it, and we'll explore these ways before diving in and writing our own projects.
There are two parts that make up any servo animation in Johnny-Five: a target and one or more segments. The target is either a servo or an array of servos. We'll go into the programmatic differences between a servo and a servo array in our first project; the basic point is that a ServoArray object in Johnny-Five allows a logical grouping and the manipulation of multiple servos—a leg, for instance, would be a logical use of a ServoArray object.
A segment is the programmatic description of a piece of animation. It is comprised of a few pieces of information: a duration, cue points, and keyframes.
A keyframe is a description of the position of the target at a given point. A keyframe has no concept of time...