The term "special effects" refers to visual or sound-based techniques used in film, television, theatre and other forms of entertainment to create an illusion of reality. These can include anything from computer generated imagery (CGI) to practical effects such as pyrotechnics, makeup, animatronics, and optical tricks. Special effects are designed to enhance the audience's experience by creating a sense of wonder or excitement through visual spectacle. They can be used in various ways, including to create fantastical creatures, depict impossible events such as flying or time travel, or simply add depth and realism to a scene.