Animal biotechnology is the use of science and engineering to modify living organisms. The animal biotechnology in use today is built on a long history; the scope of it is to make products, to improve animals and to develop microorganisms for specific agricultural uses. Some of the first biotechnology in use includes traditional breeding techniques that date back to 5000 B.C.E. Such techniques include crossing diverse strains of animals (known as hybridizing) to produce greater genetic variety. Animal biotechnology in use today is based on the science of genetic engineering. Under the umbrella of genetic engineering exists other technologies, such as transgenics and cloning, that also are used in animal biotechnology. Animal biotechnology include creating transgenic animals (animals with one or more genes introduced by human intervention), using gene knock out technology to make animals with a specific inactivated gene and producing nearly identical animals by somatic cell nuclear transfer (or cloning).