Abstract
Teletext and viewdata displays present a strong challenge to the information designer. The mono-spaced dot matrix characters are relatively crude in their design, and their positioning is determined by a fixed grid. The graphics facility is also somewhat crude. The scope for typographic and spatial coding of information is therefore very limited. There is, however, the possibility of using colour as a way of coding information. Seven colours, including white, are available, but they are not of equal brightness and this has important implications for legibility. Bearing in mind the constraints and freedoms offered by this kind of display, ways of presenting text, tables, indexes and graphics of various kinds are discussed.