Genetic engineering can help improve medicine, the environment, and agriculture. It works by locating a gene, inserting a desired trait, reproducing cells, and observing the results. Genetic engineering may help lower medical costs by increasing lifespan, preventing disease, providing affordable treatments for illnesses through gene therapy, vaccine production, and mapping the human genome. It can also help agriculture by creating genetically altered plants that are more commercially valuable and nutritious. Additionally, genetic engineering may benefit the environment by converting harmful materials, removing pollutants from land, and making plants more nutritious.