What does "hydrogen" mean?

Hydrogen is a chemical element that is abundant in the universe and appears as a colorless and odorless gas. It was discovered in 1766 by an English scientist named Henry Cavendish, who observed that hydrogen burns and forms water.

Hydrogen is often found in the form of diatomic molecules with the simple formula H2. It forms covalent bonds with a wide variety of other elements, such as oxygen, sulphur and nitrogen, generating numerous chemical compounds. Hydrogen plays an important part in the manufacturing processes of fertilizers, hydrogenated vegetable oils and rocket fuels. Because it is lighter than air, hydrogen is also used to propel balloons and dirigibles.