Bacterial conjugation is the exchange of genetic material by direct contact. It is one of the methods of horizontal gene transfer.
Unlike transduction and transformation, conjugation involves cellular contact. It is controlled by the donor plasmid. This is called plasmid mediated conjugation.
Conjugation involves delivering a plasmid to a recipient cell. Plasmids tend to contain genes that increase survival in hostile environments.
These genes can confer antibiotic resistance or can allow the bacteria to metabolise different carbon sources.