Moiré effect is a visual perception that can be created for artistic or entertainment reasons, or in my case, as a learning process as well. They create optical ilusions and effects that I haven't seen anywhere else. They can also help you understand how sound waves work fx. Interlacing shapes or sounds both create a new sound or visual effect simply out of...nowhere :) Don't you think that's a bit crazy and interesting? :) I hope I answered your question.