Hydrogen is the most common element in the universe and the first listed in the periodic table of elements. It is a colorless and odorless gas. Each atom of hydrogen contains one proton and one electron.
Approximately three-fourths of the mass of the universe is hydrogen, and yet hydrogen is the lightest of all of the elements. Discovered in 1766, hydrogen has many uses, including an important part in the manufacturing of fossil fuels and ammonia. The name hydrogen originates from the Greek language. "Hydro" means water, and "genes" means forming. Hydrogen, then, means "forming water," and, of course, two atoms of hydrogen combine with one of oxygen to make water.