Let show you an example:
To show a number, for example, 6789, will you agree with me that we will always use those numbers : 1,2,3,4,5,6,7,8,9 and 0.
Same thing for amino acids, there are 20, but they can make endless combinations.
TAG-CAA-CCC OR GGC-AAA-TAT-CCA
etc.
