Cloning is a technique of creating or duplicating genetically identical copies of a biological organism. There are several methods of cloning:

• Somatic Cell Nuclear Transfer (SCNT) – A nucleus containing genetic material is removed from any cell in the body and injected into an unfertilized egg whose nucleus has been removed. The egg is then artificially stimulated, causing it to divide and act like an embryo. The cell/organism produced by the cloning process is genetically identical to the source from which the nucleus was taken.
• Embryo Splitting – In Vitro Fertilization (IVF) is used to create a fertilized egg (zygote), which splits to become an embryo with four identical cells. The cells are separated and develop into separate but identical blastocysts that can be implanted in the uterus, mimicking the natural process of the formation of identical monozygotic twins.

Within bioethical discourse it is customary to differentiate between therapeutic and reproductive cloning. The latter raises serious ethical concerns.