If we are going to talk about animation, we had better define it. Here is one defintion:

Gene Deitch, 1978

The recording of individually created phases of imagined action in such a way as to achieve the illusion of motion when shown at a constant, predetermined rate, exceeding that of human persistence of vision

That was probably quite a good definition at the time. Animation was shown on film stock as individual frames projected on to a screen. The animator had to keep the changes from frame to frame at a constant rate if smooth motion was required.

Steven Millhauser, 1993

An immobile world of inanimate drawings that have been granted the secret of motion. Animation is the poetry of the impossible

This is more conceptual focusing on the intent of the animation but it still makes the assumption that the animation is created via a sequence of stationary images.

WHAT IS ANIMATIO W h a t   A b o u t   T h i s ?   M a y b e !

Those definitions might have been appropriate at the time but are clearly somewhat out-of-date. The modern display has such a high frame rate that persistence of vision is no longer of great importance. The SVG declarative animation has moved away at the conceptual level from the notion of frames and a predetermined rate. Instead, objects change over time with no need to specify individual inbetween frames. Independent time lines can be connected by events; in the simplest case begin this when that ends. That is the conceptual level at which users of SVG can author animations.

Our main interest early on was seeing how computer animation could be used in education. Addressing the issue below was important.

John Hallas, 1986

Animation in Education is very much underused. Moving lines, colours, shapes and symbols can represent the essence of an idea or an emotion and can express it with clarity, force or humour. With animation, ideas can be expressed using only a fraction of the time needed with conventional teaching methods. This form of visual education could be significantly expanded for the overall benefit of society.