This document discusses the Siemens WinCC Flexible human machine interface (HMI) software. It covers the components and applications of WinCC, including controller configurations with single or multiple HMI devices. The document reviews the engineering tools for configuring HMIs, including creating projects, defining tags, designing screens and graphics, setting up alarms, logging data, and creating recipes. WinCC Flexible is designed for configuring Siemens HMI operator panels and Panel PCs for industrial automation applications.