Our Sun is the nearest star and thus an ideal laboratory to study dynamic processes which are related to solar terrestrial physics. The topics addressed in this book cover solar MHD and generation of acoustic waves, as well as physical parameters that are suited to describing solar activity and could serve as proxies for space weather forecasting. The influence of solar activity (radiation and solar wind) on telecommunication systems, satellite missions etc. is also discussed. In short, contribution reports are given on various topics in solar physics. The book covers solar physics from the photosphere to space weather influences. The intended level of readership is aimed at students working in this or related fields, professionals, and astronomers who wish to acquire some basic knowledge in the field of solar terrestrial relations, which is provided in the review articles.