Once your character is modeled and rigged, you're ready to start animating. Animation is a motion-based art, and an understanding of the way objects move is very important to becoming a good animator. The laws of motion are the foundation of the science of physics, and a little knowledge of physics can go a long way toward giving your characters a sense of realism.
Motion is intimately related to time. In fact, motion is simply the change of an object's position over time. Time is a raw material that actors, comedians, and musicians use constantly. Good comic timing means knowing exactly when to spring the punchline. Good animation timing means knowing exactly when your character should react, blink, or pull that huge mallet out from behind his back. Timing is the only thing that separates animation from illustration. Developing a good sense of timing is very important to becoming a good animator.
On top of the basic physics of motion, you also have to consider the meaning of motion. A character moves his body for a reason, and these motions are very important because they convey the character's mood and personality to the audience. Only through motion can the character truly come to life.
Chapter One. Basics of Character Design
Chapter Two. Modeling Characters
Chapter Three. Rigging Characters
Chapter Four. Basics of Animation
Chapter Five. Creating Strong Poses
Chapter Six. Walking and Locomotion
Chapter Seven. Facial and Dialogue Animation
Chapter Eight. Animal Motion
Chapter Nine. Acting
Chapter Ten. Directing and Filmmaking