The chemical element with the symbol H is hydrogen. Hydrogen is the simplest and most abundant element in the universe, consisting of one proton and one electron. It is essential for the formation of stars and is a key component of water (H2O), which is vital for life. Hydrogen is highly reactive and primarily exists in molecular form (H2) in nature. It plays a crucial role in various industries, including the production of ammonia for fertilizers and in fuel cells for clean energy. Research into hydrogen's potential as a sustainable energy source is currently a significant focus in science.