During the initiation the ribosome binds mRNA at the AUG start codon and recruits an initiator tRNA carrying methionine.

During elongation the ribosome moves along mRNA in a 5' to 3' direction, and the next tRNA with complementary anticodon enters the A site.

During peptide bond formation the ribosome catalyzes peptide bonds between amino acids at the A site and the growing polypeptide.

During translocation the ribosome moves along mRNA in a 3' to 5' direction, shifting the tRNA at the P site to the A site, and the tRNA at the P site exits.