Melting is a physical phase transition in which a substance changes from a solid state to a liquid state. This process occurs when the temperature of the solid is raised to its melting point, providing enough thermal energy to overcome the intermolecular forces holding the crystalline or amorphous lattice structure together. The change of state absorbs energy, an enthalpy known as the latent heat of fusion, which is required to break these bonds without raising the temperature of the material. Different substances exhibit unique melting points, which are characteristic properties determined by the strength of their respective chemical bonds and intermolecular interactions.