What is #DeltaH# in the equation #DeltaG = DeltaH - TDeltaS#?
The change in enthalpy is equal to the energy supplied as heat at constant pressure.
The equation ΔG=ΔH−TΔS gives the free energy change accompanying a process.
The sign of free energy change tells as whether the process is spontaneous or not and it depends on the enthalpy and entropy and temperature of the system.
If ΔH is positive heat flows to the system and ΔH is negative heat flows from the surrounding.
So for the process for which ΔH is negative, ΔG is negative. So the process occurs spontaneously.