Refrigeration is the process of removing heat from an enclosed space, or from a substance, and moving it to a place where it is unobjectionable. The primary purpose of refrigeration is lowering the temperature of the enclosed space or substance and then maintaining that lower temperature. This book reviews research on refrigeration including an overview of up-to-date developments and technology in the field of magnetic refrigeration at room temperature (RTMR); an alternative approach based on artificial neural networks (ANNs) to determine thermodynamic properties of refrigerants; solar powered sorption refrigeration and air conditioning; the modelling of chilling and freezing processes and others.