Abstract: Amino acids are the organic compounds which contain amine (-NH2) and carboxyl (-COOH) functional groups, along with a side chain (R group) which is unique to each amino acid. In this paper, there is a description on how proteins are useful for living organisms. The focus is on acid- base properties of amino acids. This paper also tells about different types of amino acids and their functions. Different uses of amino acids are also mentioned significantly.