Abstract: For disease control and eradication and in countries trying to establish a disease free status, effective diagnostic is a paramount. Many diagnostics find its application throughout different levels of laboratory research processes. Polymerase Chain Reaction (PCR) is one of the most important molecular diagnostic tools which allow the detection of nucleic acid targets. Because of its excellent sensitivity, specificity and speed, PCR has rapidly become the widely used molecular biological techniques in scientific, medical and research fields. There are different types of PCRs which are used specifically for certain specific purposes. The types of PCR and their applications are discussed in this review article.