This document provides an introduction to refrigeration presented by Deepak Kumar Yadav of the ME Department at Kali Charan Nigam Institute of Technology, Banda. It defines refrigeration as the process of removing heat from a substance under controlled conditions. It discusses refrigerating effect as the rate of heat absorbed to cool a body and ton of refrigeration as a standard unit of measurement. The document also introduces heat engines, thermal efficiency, heat pumps, and refrigerators while providing key details about each topic in under 3 sentences.