Video feedback occurs when you point a camera at a display of its own output. Because of built-in processing delays, at every instant, the camera records an image that it projected about 40 milliseconds earlier. Because it records the previously projected image from some distance away, and probably at a slight angle, the recorded image is always a slightly distorted version of the projected one. The distortion gets projected on the display in turn, and then that gets recorded (with further distortions) and projected, and so on: The video output beautifully evolves.
Geometry drives evolution in video feedback. If a camera is zoomed in on its display, it continuously magnifies the projected image by stretching out the tiny details, including noise, in its center. If, on the other hand, the camera is zoomed out, then features get compressed to the center with every iteration of the feedback loop. If the camera is rotated or angled while recording its own output, then the stretching and compressing caused by the zoom happens along spiral paths. (This formula describes image distortion as a function of these various settings.)
Of course, because of the iterative, fractal nature of the video feedback effect, it isn't surprising that it causes familiar and organic patterns to emerge, as seen in the above clip.