FFT Properties can demonstrate what is the property of the signal itself and what is the property of FFT transformation. With the the signal generator built-in the user can gain insight in to the relation between the displayed signal and the actual formula used to generate it. For those reasons a FFT tutorial is included with FFT Properties with some of the signal processing basics the can be demonstrated in FFT Properties.
The user can also listen to what he is looking at. Although many sophisticated methods have been developed to analyze signals, human ear is still an analyzer beyond compare.
FFT Properties also comes with an interesting interpretation of the DFT formula. Included is also a very compact introduction to wavelet based signal analysis. Together with the The DSP for MtxVec, the user has the option to design his/hers own frequency analyzer.