Many hardware devices present either results or alternatives selected by computers to users. A few are video display terminals (VDTs), touch-tone telephones, and computer-generated speech systems. In part this book con­ cerns the impact and implications of such tools. Alternatively this is an attempt to provide material for researchers, students, and managers con­ cerned with computer interfaces. The subject of computer interfaces is at one level a technical subarea sharing common interests with the broad dis­ ciplines of computer science, psychology, and bioengineering. However, it is also a topic thrust to the forefront of interest of a wide variety of individuals who confront one of the most striking technological changes that has occurred in human history-the introduction of contact with computing devices as an essential component of many kinds of ordinary transactions. Point of entry sales, travel and entertainment reservations, and library infor­ mation, are commonly conducted today by interaction with digital calculat­ ing devices that did not exist in the recent past. The papers in this book present several concerns arising from the widespread use of computing. One involves the future implications of further advances of this technology. This is a twofold issue: (a) the potential conse­ quences of changing the basic way that information is managed in areas ranging from design, engineering, and management/planning to information access, education, and clerical function; and (b) improvements that could be instituted from further development of the special characteristics of display techniques, technologies, and algorithms.