Electronic libretto
The Electronic libretto system is used primarily in opera houses and is a device which presents translations of lyrics into an audience's language or transcribes lyrics that may be difficult to understand in the sung form.
Since 1983, projected Supertitles or surtitles have been commonly used in opera or other musical performances and they have proven to be a commercial success in art forms such as opera which are generally sung in foreign languages.
However, many people believed that surtitles interfered with the enjoyment of a performance, because they tended to find themselves following the titles and not giving their full attention to the stage. This problem was solved by the development of an electronic libretto system, which utilizes individual screens placed on the back of each seat, thus allowing patrons either to view a translation or to switch them off during the performance.