Based on preceding and C-terminal amino acid, the peptide type of a given peptide is assigned. Peptides with preceeding and C-terminal lysine or arginine are considered fully-tryptic. If a peptide is located at the N- or C-terminus of a protein and fulfills the criterium to be fully-tryptic otherwise, it is also considered as fully-tryptic. Peptides that only fulfill the criterium on one terminus are semi-tryptic peptides. Lastly, peptides that are not fulfilling the criteria for both termini are non-tryptic peptides.