The compounds formed when elements or compounds react with oxygen are called oxides. This name applies broadly to chemical compounds that contain at least one oxygen atom bonded to another element. For example, when calcium reacts with oxygen, it forms calcium oxide; when carbon reacts with oxygen, it can form carbon dioxide. Oxides result from oxidation reactions involving oxygen and the other substance.

Oxides can be basic, acidic, or amphoteric depending on the nature of the elements involved, and they play significant roles in both nature and industry.