From the video’s about page:
The 12 basic principles of animation were developed by the ‘old men’ of Walt Disney Studios, amongst them Frank Thomas and Ollie Johnston, during the 1930s. Of course they weren’t old men at the time, but young men who were at the forefront of exciting discoveries that were contributing to the development of a new art form. These principles came as a result of reflection about their practice and through Disney’s desire to use animation to express character and personality.
This movie is my personal take about those principles, applied to simple shapes. Like a cube. Check also the animated gif gallery here.