Volume 1 of the 5-volume Quantum Nanochemistry series presents an overall perspective of nuclear, atomic, molecular, and solids structures, and the observability and quantum properties as based on the quantum principles in their various levels of applications, from Planck, Bohr, Einstein, Schrödinger, Hartree-Fock, up to Feynman Path Integral approaches. The volume presents in a balanced manner the fundamental and advanced concepts, principles, and models as well as their first and novel combinations and applications in modeling complex natural or designed phenomena.