Cloning is the process of producing individual organisms with either identical or virtually identical DNA, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction. In the field of biotechnology, cloning is the process of creating cloned organisms (copies) of cells and of DNA fragments (molecular cloning).

Many organisms, including aspen trees, reproduce by cloning, often creating large groups of organisms with the same DNA. One example depicted here is quaking aspen.