Anaglyph is a technique used to create a three-dimensional (3D) effect in images or films. It involves overlaying two images, one in red and the other in cyan, which represent the left and right eye views. When viewed through special glasses with one red lens and one cyan lens, the brain combines the two images, creating the illusion of depth. This method has been popular in various media, including comic books, movies, and virtual reality. Anaglyph images can be easily produced and viewed, making them a common choice for 3D presentations, especially before the advent of more advanced technologies like polarized 3D and active shutter glasses.