dewey decimal redirects here it is not to be confused with duodecimal the dewey decimal classification ddc or dewey decimal system is a proprietary library classification system first published in the united states by melvil dewey in 1876
physical geography The scientific study of the natural features of the Earth's surface, especially in its current aspects, including land formation, climate, currents, and distribution of flora and fauna. Also called physiography.
the study of the composition, structure, and properties of matter, the processes that matter undergoes, and the energy changes that accompany these processes. the VERTICAL columns of the periodic table (1-18).