A set of measures which are taken to prevent the introduction and spreading of harmful organisms to minimise the risk of transmission of infectious diseases to organisms like people animals and plants which are caused by microorganisms such as virus and bacteria is called as biosecurity. In the field of agriculture discrimination method of bio security is maintained to protect the food crops and livestock by keeping the ham full organism such as and microorganisms affecting the crops the saving them from diseases and leading to hi crop yield and welfare of human population. Biosecurity also includes the biological threats that are common to the people which include the pandemic diseases and bioterrorism.