Pierre Rabardel's book, "Les hommes et les technologies; approche cognitive des instruments contemporains," explores the cognitive approach to contemporary instruments, emphasizing the human-centric perspective. The book is divided into several parts, each addressing different aspects of human-instrument interactions. The first part discusses the social and scientific contexts of "activities with instruments," critiquing technocentric approaches that reduce human activity to a residual role. It advocates for an anthropocentric approach that centers on the human subject and their activities. The chapter on psychological approaches to techniques and artifacts highlights the contributions of Vygotsky and others, emphasizing the constitutive role of techniques in human development and communication. The second part delves into the concept of instruments, proposing a mixed entity that combines both the artifact and the user's schemes of use. This perspective broadens the interaction model beyond the traditional subject-object dichotomy to include interactions between the subject, instrument, and artifact. The third part focuses on the developmental process of instruments, exploring how users generate and elaborate instruments through instrumentalization and instrumentation processes. This section discusses the importance of understanding these processes to better design and use instruments effectively. The fourth part examines the effects of instruments on human activity, suggesting that instruments can both structure and open up possibilities for action. It also addresses the issue of transparency in artifacts, proposing the concept of "operational transparency" to explain how artifacts are perceived and used by users. The final part applies these theoretical developments to practical areas such as analysis, design, and training, providing examples of how these concepts can be applied in real-world settings. Overall, the book advocates for a human-centric approach to understanding and designing technologies, emphasizing the active role of humans in the creation and use of instruments.Pierre Rabardel's book, "Les hommes et les technologies; approche cognitive des instruments contemporains," explores the cognitive approach to contemporary instruments, emphasizing the human-centric perspective. The book is divided into several parts, each addressing different aspects of human-instrument interactions. The first part discusses the social and scientific contexts of "activities with instruments," critiquing technocentric approaches that reduce human activity to a residual role. It advocates for an anthropocentric approach that centers on the human subject and their activities. The chapter on psychological approaches to techniques and artifacts highlights the contributions of Vygotsky and others, emphasizing the constitutive role of techniques in human development and communication. The second part delves into the concept of instruments, proposing a mixed entity that combines both the artifact and the user's schemes of use. This perspective broadens the interaction model beyond the traditional subject-object dichotomy to include interactions between the subject, instrument, and artifact. The third part focuses on the developmental process of instruments, exploring how users generate and elaborate instruments through instrumentalization and instrumentation processes. This section discusses the importance of understanding these processes to better design and use instruments effectively. The fourth part examines the effects of instruments on human activity, suggesting that instruments can both structure and open up possibilities for action. It also addresses the issue of transparency in artifacts, proposing the concept of "operational transparency" to explain how artifacts are perceived and used by users. The final part applies these theoretical developments to practical areas such as analysis, design, and training, providing examples of how these concepts can be applied in real-world settings. Overall, the book advocates for a human-centric approach to understanding and designing technologies, emphasizing the active role of humans in the creation and use of instruments.