Nucleic acids are biopolymers essential to all known forms of life. They are composed of monomers called nucleotides, which consist of a nitrogenous base, a sugar molecule, and a phosphate group. The two primary types of nucleic acids are DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). DNA stores genetic information, while RNA plays various roles, including acting as a messenger and a catalyst.