Earth Science is the study of earth and space. In other words, it is a term for the science, related to planet Earth. For the study of Earth Science, there are two approaches – reductionist and holistic. In earth science, four spheres are generally recognised, Lithosphere, hydrosphere, atmosphere and biosphere, which respectively correspond to rocks, water, air and life. Realising the need of a worthwhile book on the subject; ‘Earth Science Today’ covers all aspects the subject. We have made this humble effort in order to fill the bill. Hopefully, the students, scholars and general readers would be benefited by this work.