Autocue has become a generic term for any type of teleprompter and systems have been around since the 1950s. They are commonly used in news programmes and whenever a presenter has to read a piece to camera whilst reading a script. The script is typed into a computer and then displayed, a few lines at a time, on an LCD monitor mounted underneath the camera's lens. The words are reflected from a piece of glass held at 45 degrees to the lens so the camera can see through the glass whilst the presenter can see the script. The Autocue operator scrolls the script as the presenter reads it.
Lightweight LCD Autocue systems are often mounted on the camera allowing it to pan and tilt freely. It's also possible to arrange the screen as a free standing unit without attaching it to the camera .