The paper is devoted to problems of computer metaphors,, Such as Interface metaphor and Visualization metaphor. Interface metaphor is considered as the basic idea of likening between interactive objects and model objects of the application domain. A visualization metaphor is defined as a map establishing the correspondence between concepts and objects of the application domain under modeling and a system of some similarities and analogies. This map generates a set of views and a set of methods for communication with visual objects. Some positions of the metaphor theory are discussed. Concept of metaphor action is suggested.. "Formula" of metaphor is constructed. A set of examples of metaphor was analyzed. Aprioristic quality criteria of interface and visualization metaphors are suggested. These criteria allow evaluating as existing metaphors and to search for adequate metaphors for designing new specialized systems.