The book introduces the fundamental aspects of digital imaging and covers four main themes: Ultrasound techniques and imaging applications; Magnetic resonance and MPJ in hospital; Digital imaging with X-rays; and Emission tomography (PET and SPECT). Each of these topics is developed by analysing the underlying physics principles and their implementation, quality and safety aspects, clinical performance and recent advancements in the field. Some issues specific to the individual techniques are also treated, e.g. choice of radioisotopes or contrast agents, optimisation of data acquisition and storage, readout electronics, modelling and computer algorithms for imaging and measurement in ultrasounds and tomography applications. All topics are presented with didactical language and style, making this book an appropriate reference for students and professionals seeking a comprehensive introduction to the field as well as a reliable outlook on the most recent developments.