Movement refers to a way of combining the art elements to produce the look of action or to cause the viewerʼs eye to sweep in a certain manner or direction. Such movements can be directed along lines, edges, shapes, and colors within the works, but moves the eye most easily on paths of equal value. Because the innate physiology of the eye forces the individual to focus in on specific elements within the visual field, it is used to carry or direct the eye of the viewer from one part of the design to the other, often to focus areas. Movement encompasses the use of art elements to direct a viewer’s eye along a path through the work, and/or to show movement, action and direction. Giving some elements the ability to be moved or move on their own is also the principle at work.
Source: J. Paul Getty Museum, “Understanding Formal Analysis – Principles of Design;” Cornell University, “About Art, Design and Visual Thinking;” The Principles of Design and Organization; Jeff B. Petz, “Eye Movement and Natural Tasks”
Example from original source:

Example from different source:

Source: Melissa Mandelbaum, “Design Principles”
Real life example:

For more info: Walt Disney Concert Hall
Great examples! Movement is also a great way to show interaction design and bring an application to life. I think the best UI designs have this integrated with their designs. Here is a great example of Material Design and how they integrated movement in to their design. https://material.io/guidelines/motion/material-motion.html
Thanks, Amir! Your example of motion in Google’s Material Design is a great paradigm of this concept in use. Modern guidelines in user interface design seem to capitalize on making the experience feel entirely digital, as opposed to the skeuomorphic instances in the past, and a great way to do this is through animations. I like how Google stresses natural easing curves as “movement inspired by forces in the real world,” and elucidates on the importance of motion to describe spatial relationships, functionality, and intention. In this case, movement serves a larger purpose: it can show how an app is organized and what it can do, provide a guided focus between views, hint at what will happen if a user completes a gesture… It makes movement meaningful.