At the beginning of the twenty-first century, the age of digital recording and surround-sound, it is difficult to imagine a time when movie actors did not speak on screen. Yet during the first twenty-five years of the twentieth century, it was difficult to imagine them ever doing so. Silent movies were watched in silence or accompanied by live musicians in the theater. Speech was displayed in print (known as intertitles) on the screen between the action sequences.

Thomas Edison (1847–1931) and his assistant William Dickson (1860–1935) were the first to make moving pictures possible with their Kinematograph in 1891. Dickson later designed the Kinetoscope, a boxlike apparatus that allowed a single viewer to watch moving pictures. Early silent films, known as "actualities," lasted only a few seconds and recorded events as they happened using a fixed camera. In the late 1990s and into the early twenty-first century, reality TV...