The latent heat of fusion, Lf. This is the heat per kilogram needed to make the change between the solid and liquid phases, as when water turns to ice or ice turns to water.
The latent heat of vaporization, Lv.This is the heat per kilogram needed to make the change between the liquid and gas phases, as when water boils or when steam condenses into water.
The latent heat of sublimation, Ls. This is the heat per kilogram needed to make the change between the solid and gas phases, as when dry ice evaporates.
Thanks!