Animation is based on a principle of human vision. If you view a series of related still images in quick succession, your brain perceives them as continuous motion. Each image is called a frame.
Historically, the major difficulty in creating animations has been that the animator must produce a large number of frames. Depending on the quality you want, one minute of animation might require between 720 and 1800 separate still images. Creating images by hand is a big job. That's where keyframing comes in.
Most of the frames in an animation are routine, incremental changes from the previous frame directed toward some predefined goal. Early animation studios quickly realized they could increase the productivity of their master artists by having them draw only the important frames, called keyframes. Assistants could then figure out the frames that were required in between the keyframes. These frames were (and still are) called tweens.
Use 3ds Max as your animation assistant. As the master animator, you create the keyframes that record the beginning and end of each transformation. The values at these keyframes are called keys. 3ds Max calculates the interpolated values between each key value, resulting in tweened animation.
3ds Max is not limited to animating transformations (such as position, rotation, and scale). It can animate just about any parameter you can access. Thus, you can animate modifier parameters, such as a Bend or a Taper angle, material parameters, such as the color or transparency of an object, and much more.
Early animation studios also had to employ artists to add the ink and color to each frame. Even today, production of a cartoon usually requires hundreds of crafts people and artists to generate the thousands of images. With 3ds Max, the renderer takes over the job of shading and rendering each frame and storing it as you direct. The end result is a high-quality finished animation.
The quickest way to animate is to turn on Auto Key and start transforming objects at different frames. Each time you transform an object, you set a key. Then you can play the animation onscreen, or render it to a file.