Heat storage applications benefit greatly from phase change materials’ (PCMs) high energy storage density at a practically constant temperature. The melting points of various materials vary, thus they have lately attracted a lot of interest for use in heating and cooling buildings and providing clean hot water. This study begins with a comprehensive explanation of phase transition materials, including how they function, the many forms they may take, and their defining characteristics. Recent computational and experimental studies have shown that nanoparticles are extremely helpful for enhancing the thermophysical properties of PCMs, allowing Nano-PCMs, primarily Nano-paraffin, to have a significant positive influence on thermal concepts at the economic, ecological, and effectiveness levels.