This document discusses different models of the atom, including Bohr's model, the quantum mechanical model, and atomic orbitals. It describes key aspects of each model, such as electrons occupying specific energy levels in Bohr's model and the probabilistic nature of electron location in the quantum mechanical model. It also explains atomic orbitals in more detail, defining principal and other quantum numbers that describe orbital shape and electron location probability. Diagrams are provided to illustrate orbital shapes like s, p, d, and f orbitals.