Visible light communications : theoretical and practical foundations Visible Light Communication (VLC) is an emerging wireless data transmission technology. Light is used simultaneously for illumination as well as for communication and or positioning purposes. If fully networked dubbed Li Fi VLC systems complement Wi Fi access points. VLC is an incident of optical wireless communications (OWC). OWC systems provide high data security are license free and may substitute radio systems when these either fail or are not permitted. VLC technology enhances smart lighting infrastructure and Internet of Things (IoT) use cases. LED based Car to X communication is an enabling platform towards autonomous driving. The textbook covers OWC applications fundamentals of illumination engineering channel modeling optical intensity modulation schemes VLC standardization efforts the software defined radio concept selection criteria of photonic devices fundamental circuit designs and visible light positioning. The book is written for students in electrical and information engineering or adjacent areas as well as for engineers information scientists and physicists in research and development.