Halophiles, microorganisms that thrive in high salt environments, come in various types and are found in all three domains of life. They have diverse metabolic abilities, including producing energy through different processes. As salt levels increase, the types of metabolic processes decrease. Recent studies have greatly expanded our knowledge of halophilic microorganisms using various techniques. Some of these microorganisms are used in biotechnology, with advantages over non-halophiles in certain applications.