One of the key challenges in the small-molecule drug discovery field is to find therapeutic compounds that bind to targeted biomacromolecules with high affinity. Typical questions that need to be answered during drug discovery projects include the following: How does a drug molecule interact with the residues in the binding pocket of the protein? What is the binding affinity of a molecule? How does the molecule compare to other prospective drug candidates in terms of strength of binding energy? Knowing the answers when conceptualizing a compound can help medicinal chemists make a more informed decision about the experiments that need to be done or the compounds that need to be synthesized, thus saving a lot of time, effort and money.