When animating in a digital context, especially with Adobe Flash, the shortened term tweening is commonly used. Sophisticated animation software enables one to identify specific objects in an image and define how they should move and change during the tweening process. Software may be used to manually render or adjust transitional frames by hand or may be used to automatically render transitional frames using interpolation of graphic parameters. In the context of Adobe Flash, inbetweening using automatic interpolation is called tweening, and the resulting sequence of frames is called a tween.
"Ease-in" and "ease-out" in digital animation typically refer to a mechanism for defining the 'physics' of the transition between two animation states, eg the linearity of a tween.
The use of computers for inbetweening was pioneered by Nestor Burtnyk and Marceli Wein at the National Research Council of Canada. They received a Technical Achievement Academy Award in 1997, for "pioneering work in the development of software techniques for computer assisted key framing for character animation".