Audio Visual (AV) means possessing both a sound and a visual component, such as slide-tape presentations,films, television programs, church services and live theater productions.Business presentations are also often audiovisual. In a typical presentation, the presenter provides the audio by speaking, and supplements it with a series of images projected onto a screen, either from a slide projector, or from a computer connected to a projector using presentation software. Audiovisual service providers frequently offer web streaming, video conferencing and live broadcast services.Computer-based audiovisual equipment is often used in education, with many schools and universities installing projection equipment and using interactive whiteboard technology.