Introduction The world we live in is a marvel of man′s mastery over his environment. Through the explosive development of the science, we are able to predict, control and understand the different phenomena happening around us. The scientific revolution has maximized opportunities for human happiness, and through its technical arms, is providing material wealth and long and healthy lives. The effect of science on human life and thought has become so great. What is Science? Etymologically, the word ′science′ comes from the Latin word, ′Scientia′ which means knowledge or to know. Huxley defines science â€�as trained and organized common senseâ€�. In the literal sense, science means the pursuit of knowledge but it has a wider connotation for our purpose, and can be said to mean knowledge of nature in the widest possible form. This includes astronomy, physics, chemistry, micro biology, bio chemistry, and much more. Science includes all knowledge communicable and verifiable obtained by methodical observation and experiment. We can define science in different ways as: Å� Science is a systematized body of knowledge. Å� Science is nothing but an organised common sense. Å� Science is a heap of truth. Man is inquisitive by nature. He is always in search of the `How and Why′ of all that happens in nature and in his surroundings. His spirit of enquiry at first extends to most simple facts of nature. A child would like to know, how a small seed grows into a huge tree. As he grows up, he comes across more complicated events and objects. He enquires how pictures are seen in a television, why clouds are moving from one place to another? â€� and so on. In this way human mind is always active in the pursuit of exploring the unknown. Science can be termed as the process of fulfillment of the spirit of enquiry or the modalities adopted in diving deep into the complexities of nature. Man by his keen observation skill and reasoning ability has come to the conclusion and stated that there cannot be any event in nature without any reason. There is a universal law of ′cause and effect.′ If there is an epidemic of disease there must be a cause for it. Man wondered how day and night are caused. By applying the law of cause and effect, he found that day and night are caused due to the rotation of the earth round its axis.