Digital Video Discs can store videos in near studio quality or audio in a very high quality. A DVD is approximately equivalent to 3 CDs ie.2.5GB and the speed of the movie would be 300mb/hr approximately.
Text and slides are basically HTML documents and powerpoint presentations of the courseware.
Digital audio comes in different formats namely WAV and MPEG formats.
Streaming video is a sequence of "moving images" that are available in compressed form. Streaming media is streaming video with sound.
Hypertext is ordinary text that has been dressed up with extra features,such as formatting, images, multimedia, and links to other documents. HTML documents can be delivered by the same means as any other computer file.