A restriction map is a kind of a physical map. It consists of a piece of DNA with restriction sites specific for endonucleases. The number of bases decides the sites of separation. Restriction enzymes create two types of ends such as sticky or blunt ends. A staggered cut in the restriction site with symmetrical nucleotide sequence generates sticky ends. There are two types of ends such as 5’ or 3’ overhanging ends. When a restriction enzyme cuts at a symmetrical nucleotide sequence of a restriction site between the two base pairs, the blunt ends get created. When the DNA gets digested with the restriction enzymes, and the resultant fragments get separated on a gel, the banding patterns are visible after staining. They are known as restriction fragment length polymorphisms (RFLPs). Sometimes the restriction sites vary in different individuals. A restriction enzyme cleavage site present in an individual may be absent in another individual. RFLPs help in mapping the genes or polymorphic sites. However, the non-polymorphic sites get missed. Restriction mapping solves this problem. A single restriction enzyme or combination of restriction enzymes cleave the DNA efficiently. Thus we obtain the fragments of different sizes measured in kilobases. The electrophoretic gel separates the fragments based on their sizes. Autoradiography helps to visualize the bands and cut the desired portion of the gel to take the DNA fragment.