Tis book provides an overview of X-ray technology, the historic developmental milestones of modern CT systems, and gives a comprehensive insight into the main reconstruction methods used in computed tomography. Te basis of reconstr- tion is, undoubtedly, mathematics. However, the beauty of computed tomography cannot be understood without a detailed knowledge of X-ray generation, photon- matter interaction, X-ray detection, photon statistics, as well as fundamental signal processing concepts and dedicated measurement systems. Terefore, the reader will ?nd a number of references to these basic disciplines together with a brief introd- tion to the underlying principles of CT. Tis book is structured to cover the basics of CT: from photon statistics to m- ern cone-beam systems. However, the main focus of the book is concerned with - tailed derivations of reconstruction algorithms in ?D and modern ?D cone-beam systems. A thorough analysis of CT artifacts and a discussion of practical issues, such as dose considerations, provide further insight into modern CT systems. While mainly written for graduate students in biomedical engineering, medical engine- ing science, medical physics, medicine (radiology), mathematics, electrical eng- eering, and physics, experienced practitioners in these ?elds will bene?t from this book as well.