The networking of physical devices, including their infrastructure and data, is known as the Internet of Things. The number of networked devices is con- stantly increasing over the last years and is expected to continue to rise in the future. This also results in an increasing number of attacks on these devices which are considered potentially insecure. The reasons for the lack of cyber- security are diverse and lead, for example, to botnets and similar problems. Mandatory standards and guidelines can help to ensure cybersecurity re- gardless of a fast pace of development and a low price of the devices. In some areas, the development of these guidelines is already well advanced, ideally across countries as a European standard. However, problems with standardiza- tion are the different definitions of device categories and thus, the assignment of a device to a standard. Even in academia, definitions and categories for Internet of Things devices are ambiguous or completely lacking. This makes it difficult to find relevant publications. Therefore, a model of the Internet of Things was researched to solve these problems and define clear categories. The model divides the Internet of Things into categories, supplements the definitions with characteristics and distinguishes the different device types. The architectures and associated components are also considered. The model can be applied to all devices and available cybersecurity standards which is shown by mapping them to the model. The real-world applications are diverse and illustrated as different use cases. As digitalization evolves rapidly, the researched model is designed to adapt flexibly to new developments.