Solids are one of the fundamental states of matter characterized by their fixed shape and volume. Unlike liquids and gases, solids have closely packed particles that vibrate in place, giving them structural integrity. Common examples of solids include metals like Iron and non-metals like Carbon in its diamond form. The study of solids encompasses various subfields, including Crystallography, which examines the arrangement of atoms in crystalline solids. Understanding the properties of solids is crucial in many applications, from construction materials to electronics, as their behavior under different conditions can significantly impact performance and safety.