1. A method of providing functions within an industrial automation system, the method comprising: providing automation functions of the automation system by a plurality of control units as web applications which are combinable by a client during control program execution to form interlinked web applications on a user interface of the client, each web application comprising at least one application component which generates at least one component instance and each control unit comprising at least one web server configured to provide the automation functions as the web applications; providing access to the web applications via: a standard application programming interface that comprises a cross-component application programming interface configured to initialize and unload application components, and a component-specific application programming interface configured to handle one or more events and provide component functions; and assigning each of the application components metadata operative for declaring functions and dependencies, wherein: each application component comprises a data interface for data access by another application component, and the component instances are linked by an application programming interface configured to stipulate interactions between application components.