The program was considered to be groundbreaking in the field of computer animation when it was initially released, and was very popular in the late 1980s and the early 1990s. Eventually development on the product ended and it became no longer supported by Autodesk.
Animator gave the ability to do frame-by-frame animation (creating each frame as an individual picture, much like traditional cel animation). "Animator Studio" also had tweening features (transforming one shape into another by letting the computer draw each in-between shape onto a separate frame).
While "Animator" and "Animator Pro" supported only the input and output of FLI and FLC animation files, "Animator Studio" supported also the input and output of the AVI animation format.