The smallest and lowest element in the periodic system. It consists of negatively charging electron and positively charging proton. Hydrogen is the most common element of space; and because of its high reactive ability, it almost exclusively appears in the compounds. Such are waters and carbon hydrates, but natural gas and crude oil. In free form, hydrogen is only in the atmosphere and fire gases. Hydrogen is a gas without colour, odor and taste.
Without Hydrogen, man would not have stepped on the moon. It forms explosive mixtures with air. In practice, it has proven to be very predictable and at least as safe or even safer as gasoline and natural gas.