A Positive Displacement Compressor is a type of mechanical device that increases the pressure of a gas by reducing its volume. It works by trapping a fixed amount of gas and then forcing it into a smaller space, which raises the pressure. This process is commonly used in various applications, including refrigeration, air conditioning, and industrial processes. There are two main types of positive displacement compressors: reciprocating compressors and rotary compressors. Reciprocating compressors use a piston to compress the gas, while rotary compressors use rotating elements. Both types are known for their efficiency and ability to handle high-pressure applications.