Environment means the, water, air, plants, animals, solid wastes and other things which surround us constitute environment. man and environment are closely intertwined in each other to maintain balance in nature. different group of people working in different areas express it in various ways. when physical scientists talk about environment they generally refer to physical environment that comprises of 3 interlocking systems atmosphere, hydrosphere and lithosphere. biological scientist always talk about biological environment consisting all living organism of biosphere. similarly social scientist refer to the social, cultural, economic and organizational environment.Hence environment may be defined as the "the sum of all biological, physical, cultural,economical, social and chemical factors that surrounds 'man' to provide him protection.