This book addresses soil mechanics and its applications in construction practice (geotechnics, foundation engineering, specialized deep construction, tunneling). Soil, as a granular material, occupies an intermediate position between solids and fluids. Therefore, soil mechanics is not only practically relevant but also one of the most interesting fields for research. The interactions of soil with water make soil mechanics theoretically even more challenging and practically even more important. At a time when regulations and standards are becoming overwhelming, understanding the underlying concepts is more crucial than ever. The author places great emphasis on their clear presentation, both in theory and in practice, which is rapidly evolving in geotechnics. Outdated theories and construction methods have been omitted, providing insight into the diverse peripheral areas.