maam can u please explain lattice enthalpy

Lattice enthalpy is the energy released when one of the ionic compound formed from its isolated gaseous ions 'examples

Na⁺ (g) + Cl^-(g) ------> NaCl (s)
Ions in ionic compounds are arranged in a repeating regular manner which is called as lattice.When a lattice is formed ,attractive forces are made and energy is released.This energy is called as lattice enthalpy.