ABSTRACT
During the 1990s the development of multimedia entered a new phase. While the first generation of multimedia in the 1980s had been built on stand-alone personal computers accessing text, sound and images from CD-ROM disks, the second generation in the 1990s was to be based on computers linked to existing communications infrastructure. In this process the development of new multimedia technologies became linked with a technological and institutional infrastructure established by the telecommunications industry over the course of the previous century. This infrastructure is based on both wired and wireless transmission technologies and in comparing these two different transmission media, it is important to focus on their similarities rather than their differences. In this context all radiant energy travels in waves, and, as James Clerk Maxwell discovered in the 1860s, radio and light waves are both
electromagnetic radiation, travelling at the speed of light and differing only in the frequency at which they vibrate. Electric current is not the same as electromagnetic radiation. The electrons that constitute it move a lot slower than light. None the less information can be propagated along a wire by an electric current at the speed of light in the same way as radio waves can be radiated. When this is realised the distinction between wired and wireless transmission becomes less clear-cut.
