Genetic information is stored in long molecules with the abbreviated name of genetic code which is a code consisting of three letters often referred to as codons in the strand of DNA.
Each code contains three letters in a unique combination each of which refers to a particular amino acid i.e. the three letter codon interprets for a single amino acid .
There are codes that indicate for the start and end of the polypeptide chain that will be formed resulting from the template DNA which first gets converted to m-RNA and then this strand contains the code for the resulting polypeptide chain.