Motion lines

In comics, motion lines (or movement lines or action lines or speed lines or zip ribbons) are the abstract lines that appear behind a moving object or person to make them look like they're moving quickly. The use of motion lines may have been inspired from both mathematical vectors, which are used to indicate direction and force, and from long-exposure photography, where a camera can capture lights as they move through time and space, blurred along the direction of motion.

Trait de mouvement