The scientific community in Italy has, for three decades now, devoted a lot of effort to realizing and maintaining several data centers in southern Italy. This has been possible thanks to the financial support from European and National institutions, particularly in the cities of Bari, Catania, and Napoli, where there are large communities of scientists working in the fields of physical sciences, chemistry, biology, genetics, engineering, ICT, and many other disciplines which use both HTC and HPC resources massively. In 2015, the Ministry of Universities and Research issued a national Call for Proposals, named "Avviso 1275", using funds largely provided by the European Union. A community of people from INFN, CNR, INAF, INGV, and the Universities of Napoli "Federico II", Bari "Aldo Moro", worked together to prepare a robust proposal, and this is the birth of the IBiSCo project. The proposal was accepted, and granted a total of about 14 million euros, to be shared among the partners. This book presents the results of the project, which over five years has increased the computational and storage capabilities of all the partners. A first series of papers, from each local representative, describes the acquisitions made in terms of hardware resources, network infrastructures, power and cooling systems, and so on. The resulting, improved, Data Centers of the project are described in detail. The second and major part of the book consists of papers reporting the scientific usage of Data Centers, from a plethora of scientists all over Italy. It should be pointed out that those contributions appear relevant not only from a scientific point of view: the IBiSCo project has allowed us to gather scientists working on quite different disciplines and to acquire hybrid resources able to accommodate computing requests very different from each other. The interdisciplinary nature of the project is testified by the coexistence of research activities spanning a wide range of research fields: biological physics, nuclear and subnuclear physics, quantum algorithms and many body systems, astrophysics, cultural heritage, Earth observation and ground deformation analyses, complex fluid dynamics, large-scale simulations of biological systems, Artificial Intelligence, management of open access repositories, bioinformatics, genetics, material physics, and design. All these activities have highly benefitted from the access to the IBiSCo resources. The book is therefore a testimonial of the huge efforts of the Italian scientific community to create and maintain in the South of Italy a network of computational infrastructures and a network of scientists using them. Notes: The book is ready for printing on paper with a size of 17x24 cm. To print on paper of different sizes, after downloading the PDF file, please use the resize option provided by the printing tools.