Sometimes information cannot be conveyed by words alone. Librarian:, hive extensively made use of the audio and visual form the new technology to their advantage. Sound recordings on tape, reel-to-reel or cassette and audio cassettes have been of great help to libraries especially in providing services to the blind. In recent years, visual aids too have come to be used especially in educating the users in use of library services.
The commercial and institutional production of visual and audio aids to education has become so substantial that many libraries are going for them. The British Library has compiled ad published a bibliography called the British Catalogue of Audiovisual Materials.
Videotapes were the first to come to market and were later replaced by video discs. Both the tapes and discs have considerable potential value as sources of information. Presently the Compact Discs are capturing the market as they have the advantage of high quality of sound and vision. The value of the audio-visual materials in libraries thus cannot be disputed.