Peptide is compound consisting of two or more amino acids linked in a chain, the carboxyl group of each acid being joined to the amino group of the next by a peptide bond. The word “peptide” itself comes from πέσσειν (peptós), the Greek word meaning “to digest.” Peptides are an essential part of nature and biochemistry, and thousands of peptides occur naturally in the human body and in animals. In addition, new peptides are being discovered and synthesized regularly in the laboratory as well. Indeed, this discovery and innovation in the study of peptides holds great promise for the future in the fields of health and pharmaceutical development. Polypeptide consist of 10-50 amino acids residues are called peptides; peptides contain more than 50 amino acids often refer as protein. Peptides can be naturally or synthetically obtained, comprising of two or more amino acids linked through an amide formation. The chemical bond (covalent bond) formed between a nitrogen atom of one amino acid to a carboxyl group of another amino acid. Peptides can be distinguished with protein on the basis of number of amino acids. The dipeptides are known as shortest peptides which contained of two amino acids connected to each other through a single bond known as peptide bond. Peptides often classified by function or by synthesis.