$DNA$ transposition is the process, which involves the movement of $DNA$ elements from one site in the genome to the other: It is mediated by transposase enzymes. These short segments of $DNA$ ($DNA$ elements) with remarkable capacity to move from one location in a chromosome to another, are called transposons or jumping genes or transposable elements or mobile genetic elements. These were first discovered by Barbara McClintock in maize $($Zea mays$)$ for which she got the Nobel Prize for physiology and medicine.