For featurisation, various properties of odorants are encoded differently. Fingerprint features mainly capture physical properties such as freezing point, boiling point, density, solvation properties, and molecular attributes . According to the vibrational theory of olfaction, a molecule's infrared vibrational frequency and its olfactory characteristics are strongly correlated . Hence, VS is also used as a feature for odor classification. The physicochemical features capture molecular structure parameters, but they cannot be used for chemical mixtures; mass spectrum can express the mixture; hence, it is also used as a feature . Some commonly used fingerprint features in recent studies include physicochemical properties and SMILES representation. Tools like Mordred (open source) and Dragon (closed source) can generate thousands of physicochemical properties for each molecule, including details about functional groups, atom types, topological indices, and ring descriptors, among other molecular characteristics, and they are used for ML/DL analysis . The cheminformatics program RDKit can also be used to calculate the Simplified Molecular-Input Line-Entry System (SMILES), another popular technique . From a SMILES representation, we can derive molecular fingerprints, which come in two types: bit-based fingerprints, which are binary representations indicating the presence or absence of certain substructures in the molecule, and count-based Morgan fingerprints (CFP), which provide counts of particular substructures in the molecule, offering a more detailed representation. These methods and tools are crucial for analyzing and characterizing molecular structures in cheminformatics .