Here is a handy reference table that lists the 20 amino acids, the codons that call for the amino acid and the three letter designation for each amino acid.
The genetic information necessary for building proteins is encoded in series of three mRNA nucleotides. Each combination of three mRNA nucleotides is called a codon. EAch codon codes for a specific amino acid.
This chart lists the 64 codons and the animo acids they code for. Also included is the three letter designation for each amino acid.