There are four laws of thermodynamics:

Zeroth law of thermodynamics: If two independent systems are each in thermodynamic equilibrium with a thrid independent system, then the first two systems must be in thermodyanmic equilibrium with each other.

First law of thermodynamics: Energy is neither created nor destroyed.

Second law of thermodynamics: The entropy of the universe increases following every reaction.

Third law of termodynamics: At a temperature of 0 Kelvin (absolute zero), the entropy of the crystal is 0.