Biology reminder
Thus, all the information needed for protein synthesis is contained in the DNA, coded by the succession of the four types of base.
Since there are 20 different types of amino-acid, a minimum of three bases are needed to code one amino-acid. This three-base sequence is called codon.
By definition, a codon can code up to 64 different amino-acids : there are several ways to code a single amino-acid and some codons are used as control sequences.