What is Character of oxides?

A basic oxide reacts with water to give a hydroxide, or with acids to give salts ($\ce{Na2O}$, $\ce{CaO}$); an acidic oxide reacts with water to give an acid, or with bases to give salts ($\ce{CO2}$, $\ce{SO3}$, $\ce{P4O10}$); an amphoteric oxide reacts with both acids and bases ($\ce{Al2O3}$, $\ce{ZnO}$). Across a period, oxides go from basic (metals, left) to acidic (non-metals, right).