The term child actor is generally applied to a child acting in motion pictures or television, but also to an adult who began his or her acting career as a child; to avoid confusion the latter is also called a former child actor.
Closely associated is teen actor, an actor who reached popularity as a teenager.
Examples (movies they appeared in are mentioned only if they were still a child):
For estimating the age at the time of shooting, note that above the years of release are given.
The term "child actor" carries some stigma as child actors sometimes have troubled adult lives, due in part to their unusual upbringings. A well-known example of this is the child cast of the 1980s sitcom Diff'rent Strokes. Child members of that cast grew into adults who had several run-ins with the law, and one member died of a drug overdose.
On the other hand, there are child actors who had successful careers in adulthood like Roddy McDowall and Bill Mumy.