This review provides an overview of the Glauber Model in relativistic heavy ion physics, focusing on its theoretical background, experimental techniques, and phenomenology. The Glauber Model is used to calculate geometric quantities such as impact parameter ($b$), number of participating nucleons ($N_{\text{part}}$), and number of binary nucleon-nucleon collisions ($N_{\text{coll}}$). The history of the Glauber model is discussed, highlighting its development from a quantum mechanical approach to a classical, geometric picture. Distinctions are made between the "optical limit" and Monte Carlo approaches, which are often used interchangeably but have essential differences. The methods used by the four RHIC experiments (BRAHMS, PHENIX, PHOBOS, STAR) are compared, showing similar results for various geometric observables. The review also highlights several important RHIC measurements that rely on Glauber calculations to draw insights from experimental data. Finally, the current status and future prospects of Glauber modeling in heavy ion physics are briefly discussed.This review provides an overview of the Glauber Model in relativistic heavy ion physics, focusing on its theoretical background, experimental techniques, and phenomenology. The Glauber Model is used to calculate geometric quantities such as impact parameter ($b$), number of participating nucleons ($N_{\text{part}}$), and number of binary nucleon-nucleon collisions ($N_{\text{coll}}$). The history of the Glauber model is discussed, highlighting its development from a quantum mechanical approach to a classical, geometric picture. Distinctions are made between the "optical limit" and Monte Carlo approaches, which are often used interchangeably but have essential differences. The methods used by the four RHIC experiments (BRAHMS, PHENIX, PHOBOS, STAR) are compared, showing similar results for various geometric observables. The review also highlights several important RHIC measurements that rely on Glauber calculations to draw insights from experimental data. Finally, the current status and future prospects of Glauber modeling in heavy ion physics are briefly discussed.