Lead is an effective shielding material against various types of ionizing radiation, particularly gamma rays and X-rays. This effectiveness stems from its high density (leading to a large number of atoms per unit volume) and high atomic number (Z=82). These properties increase the probability of interaction between the radiation photons or particles and the atoms of the shielding material, leading to absorption or scattering of the radiation. While other dense materials can also provide shielding, lead is often preferred due to its cost- effectiveness, relative ease of handling and molding, and proven performance.