Appendix A, "Digital Representation of Sound", provides a brief explanation of how sound is represented digitally. An understanding of the basic principles introduced here (such as digital sampling, sampling rate, and sample size) will be helpful in using Canary or any other sound analysis software.

Appendix B, "A Biologist's Introduction to Spectrum Analysis", provides some conceptual background for making and interpreting spectrograms and spectra with Canary. It introduces the short-time Fourier transform (STFT), the mathematical technique used by Canary for making spectrograms. A second aim of this appendix is to explain some of the limitations and tradeoffs intrinsic to spectrum analysis of time-varying signals. The discussions in this appendix assume a basic understanding of how sound is recorded and represented digitally. If you are not already acquainted with concepts such as sampling rate and amplitude resolution (sample size), read Appendix A.