DNA encodes information using groups of three bases called codons.  There are 4 different bases in DNA: A, C, G, and T.  These bases can be combined into 43, or 64, different triplets.  Each triplet codon codes for an amino acid.  Amino acids are the building blocks of proteins.  All proteins are made by stringing amino acids together into long chains.  There are 20 different amino acids. Although there are 64 possible codons, many code for the same amino acid.