A teleprompter consists of a "screen" that displays the text and can be set to scroll at a certain speed. More often, a professional teleprompter operator is responsible for using an attached knob to control the rate at which the words travel up the monitor. Many can be programmed with additional features. "Active Read" lines--what the person is actually intending to say--can be separated from directional information, such as Pause, Read List Slowly. These can be set apart by highlighting, underlining, capitalizing, changing color or text size. Teleprompters may allow editing text on-site, "bookmarking" a place in the scrolled script or arranging and linking separate sections into a cohesive final version.
Placement of the teleprompter, the distance between the subject doing the reading and the teleprompter depends on a variety of factors, including what the teleprompter is being used for. In all situations, space, size and the general eyesight and ability of the speaker should be taken into consideration. In television, the teleprompter placement will have a lot to do with the composition of the shots. Often in newscasts the teleprompter is to the side of the camera, while in other instances the words may be reflected in a mirror directly in front of the camera lens that does not interrupt the shot. In public speaking, the teleprompter is mostly hidden from view but accessible to the speaker. For motion shots in film where the camera itself is moving, a teleprompter can be attached to the tripod holding the camera via a mounting plate.
Rehearsals are useful and necessary when using a teleprompter to address concerns such as rhythm, timing and pronunciation. Rehearsals also provide an opportunity to simplify language or alter the order of words to ease the speaker's job while maintaining the desired spirit and flow of what is being said. The teleprompter operator should be adept at varying the speed of the machine's scrolling words to meet the speaker's pacing, slowing the scrolling motion down or speeding it up. Other considerations include the length of certain words and passages.
The most common use of teleprompters in television is by anchors during a newscast. Special teleprompter applications and software have been created to allow a text to appear on several cameras at once. Another instance is talk shows or interview segments, where the teleprompter screen is positioned so it appears to the viewer that the two people talking are facing one another. For performers in scripted shows, teleprompters can even come in handy when memorization is required.
Some musicians and vocal artists have used teleprompters for the purpose of helping with lyrics. Conference Teleprompter Systems, or presidential teleprompters, are heavily utilized by politicians in public addresses. Professionals use teleprompters in important meetings, conferences and at trade shows. (President Herbert Hoover made the invention well-known when referencing it at a convention.) Documentary filmmakers have been known to employ the same interview-style techniques as television hosts.
Using a teleprompter requires extra attention because it is often utilized in a hectic or distracting environment, with a lot of personnel tending to various aspects of production or presentation.