An oxide is a chemical compound that consists of at least one oxygen atom bonded to another element. These compounds can form with metals, nonmetals, and metalloids, resulting in a wide variety of substances. Common examples include water (H₂O), which is a vital oxide for life, and carbon dioxide (CO₂), a gas produced by respiration and combustion. Oxides can be classified into two main categories: metal oxides and nonmetal oxides. Metal oxides, like iron oxide (Fe₂O₃), are often solid and can conduct electricity, while nonmetal oxides, such as sulfur dioxide (SO₂), are typically gases or liquids. These compounds play essential roles in various chemical reactions and industrial processes.