Biotechnology is a multidisciplinary field that utilizes living organisms to develop products and processes. It has a long history dating back to ancient times when early humans selected plants for food and developed animal farming and food preservation techniques. Modern biotechnology applies techniques such as recombinant DNA, gene cloning, monoclonal antibodies, PCR, and genetic engineering to produce genetically modified organisms for applications in agriculture, health, industry, and environmental remediation. Biotechnology draws upon disciplines including biochemistry, bioinformatics, engineering, genetics, microbiology, molecular biology, mathematics, and statistics. It has various branches including agricultural, aquatic, energy, and health biotechnology.