A fundamental challenge to our understanding of the universe, the quantum nuclear many-body problem lies at the heart of low-energy nuclear physics. Written by two highly regarded researchers and theorists, this work provides a brief description of modern nuclear forces, and their application in finite nuclei, along with an overview of several many-body techniques, including Quantum Monte Carlo, Configuration Interaction, and coupled cluster methods. The book also focuses on high-performance computing aspects, parallelization methods and libraries, and basic quantum many-body training, while also covering the key algorithms needed to build computer codes for simple problems.