The significance and relevance of documenting process engineering systems are constantly increasing. Due to cost reductions by companies, an increase in the variety of options, and shorter delivery times, there is a heightened need for planning and control, resulting in larger volumes of data. Without computer-assisted operations management, this flood of information would be unmanageable. Databases are necessary to facilitate administration. In the field of process engineering, this means a flawless plant coding along with the corresponding P&ID diagrams. This book aims to engage and convince both insiders and those who have little insight into this topic. It is particularly important to find a common language for engineers, purchasers, technicians, and business economists.