A 3D movie is a film that creates the illusion of depth, making images appear more lifelike. This effect is achieved by showing two slightly different images to each eye, mimicking how humans perceive the world. Viewers typically wear special 3D glasses that filter these images, allowing the brain to combine them into a single three-dimensional picture. The technology behind 3D movies has evolved over the years, with various methods like anaglyph and polarized 3D being used. Popular in theaters, these films enhance the viewing experience, making action scenes and animated characters feel more immersive and engaging for audiences.