Explain "Latent heat of fusion."

The specific latent heat of fusion, l, of a substance is the heat needed to change a mass of 1 kg the substance from a solid at its melting point into liquid at the same temperature.
The enthalpy of fusion of a substance, also known as (latent) heat of fusion, is the change in its enthalpy resulting from providing energy, typically heat, to a specific quantity of the substance to change its state from a solid to a liquid, at constant pressure. For example, when melting 1 kg of ice (at 0°C under a wide range of pressures), 333.55 kJ of energy is absorbed with no temperature change