It has been shown that the language of some scientific disciplines is highly metaphorical, but there is probably no field that uses metaphor quite as pervasively and idiosyncratically as does computer science. One senses that this phenomenon results from a need to compensate for the exceedingly abstract nature of the discipline. The central metaphors do not exist singly. They exist in groups or families, suggesting a deep influence on the way people in computer science write and talk. Such a cluster of deep metaphors can be thought of as a paradigm of the discipline, a set of eyeglasses through which we see our world. This article examines some essential paradigms of computer science. These paradigms are so much a part of the way we think about and talk about computers that it is difficult to imagine computer discourse without them.