It is the first molecular marker for PCR based genetic-mapping as well as DNA-fingerprinting. In the field of genetic mapping PCR-based markers are considered as second generation molecular markers.RAPD markers are short of length (approx10nucleotides only). RAPD needs only one primer instead of a set of primers for amplification. It does not require any prior information about the DNA sequence of the desired organism. Polymorphism i.e. relatively variable DNA sequences between different species,occurs due to mutation or rearrangements either at or in between the primer binding sites. PCR products are represented by electrophoresis and visualized by ethidium bromide staining. It is a quick, simple and efficient technique as it does not involve blotting or hybridization steps. Requires only small amount of DNA (10 ng/reaction) and the process can be automated. Primers are non species specific and can be universal. RAPD products can be cloned, sequenced and converted to other types of markers (SCAR,SNP).