For undergraduate courses in Human-Factors Engineering, Human-Computer Interaction, Engineering Psychology, or Human-Factors Psychology. Offering a somewhat more psychological perspective than other human factors books on the market, this text describes the capabilities and limitations of the human operator-both physical and mental-and how these should be used to guide the design of systems with which people interact. General principles of human-system interaction and design are presented, and included are specific examples of successful and unsuccessful interactions. It links theories of human performance that underlie the principles with real-world experience, without a heavy engineering-oriented perspective.