Invisibility is the state of an object that cannot be seen. An object in this state is said to be invisible (literally, "not visible"). The term is often used in fantasy/science fiction, where objects cannot be seen by magical or technological means; however, its effects can also be demonstrated in the real world, particularly in physics and perceptual psychology classes.

Invisible is a children's novel by the Carnegie Medal-winning author, Robert Swindells, about two twins, Carrie and Conrad, who learn how to become invisible when they befriend Rosie, the new girl at school. When Rosie's dad becomes a suspect in a local crime, the gang decide to go invisible to find the real crooks. They realise something is going to happen and must put an end to it.