QSAR is based on the idea that similar structural properties generate similar biological effects.
ChemProp is not a single piece of software, but comprises several different modules. The availability of them, and thus of the features described here, may depend on a particular edition. Currently, there is a public free edition based on developments within the former EU Integrated Project OSIRIS. Furthermore, there is a professional version covering all features including batch processing in terms of QSAR runs for compound lists.