Computer aided study of the molecular biology is molecular docking. Docking is a method that predicts the ideal alignment of one molecule to another when bound forms a stable complex. The docking method is very useful for predicting both the strength and type of signal produced by the formed stable complex. The binding interaction of a ligand and protein results in activation or deactivation of enzyme. In the similar way the action of a drug and its path of action can be known through docking. Thus it plays an important role in the design of drugs. It predicts the binging of the drug to their desired targets and in-turn predicts the affinity of the drug. The structure of the protein of interest is known by biophysical techniques such as NMR spectroscopy and x-ray crystallography. This known structure and the potential ligand database serves as the input for a docking database.