A model of computer-manual comprehension is proposed in which four processes operate simultaneously: task-mapping of the structure of regular procedures onto the structure of computer commands, constructing a mental model of the computer system, inducing the command language grammar, and learning the structure of computer procedures. Findings from a study of five novices' comprehension problems with UNIX documentation are analyzed in terms of these four processes. Two of the four processes -- task-mapping and procedure learning -- are described in this paper. The analysis focuses on the knowledge structures involved in comprehending a technical test.