Multimedia is the combined use of several media, such as video, graphics, sound, lighting and text for the purpose of education or entertainment. More specifically, it refers to the use of digitized media displayed on a computer. The growth of multimedia has been spurred by a combination of factors, including the increasing power and falling prices of personal computers since the mid-1980s and by the storage capacity of CD-ROM.
While text requires little storage space, graphics, sound and video require much more. CD-ROM, by providing over 600 MB of storage on a convenient disk, enables a producer to include the entire text of an encyclopedia, thousands of images and a reasonable amount of video (about 1 hour of compressed video per disk).
By 1995 almost every desktop computer was being shipped with a CD-ROM drive, and the software and hardware needed to deliver multimedia has developed into a billion dollar industry. CD-ROMS, however, are quickly being overtaken by the new DVD technology. The DVD can store 4.7 gigabytes of information compared to the CD-ROM's 650 megabytes. Moreover, data can be written on two layers, increasing the amount of information to 8.5 gigabytes. Given that writing can be done on both sides of the DVD, this further increases its possibilities to 17 gigabytes. However, the quantity of information is not the only advantage of the DVD. Quality of sound and video approach or equal broadcast standards, thus the video industry will likely feel the impact of DVD first.