The element represented by the symbol 'H' is hydrogen. Hydrogen is the first element on the periodic table and has an atomic number of 1. It is the simplest and lightest element, consisting of one proton and one electron. Hydrogen is a colorless, odorless gas at room temperature and is highly flammable. It plays a critical role in the universe, being the most abundant element, primarily found in stars, including the sun, where it undergoes nuclear fusion to form helium. Hydrogen is also an important component in various chemical compounds, including water.