Phi Phenomenon

Does the picture seem like its rolling or moving?

Animation, films and online video all depend on optical illusion known as the phi phenomenon. 
The phi phenomenon is a perceptual illusion in which a disembodied perception of motion is produced by a succession of still images. The visual system doesn't really see motion at all it sees edges at different positions in space and makes the assumption that they are moving, like the picture above its just a still image but that way its positioned, the lines and spaces makes it seem like its moving.

Reference
https://www.scientificamerican.com/article/reality-check-10-practical-applications-of-illusions/