Signal analysis is the extraction of information from a signal. For example, identifying and isolating features of interest in an experimentally observed function.
Perhaps the most common form of signal analysis is the Fourier transformation of a temporal signal into the frequency domain to obtain the frequency spectrum of the signal. Many other transforms can be used for signal analysis, in particular time-frequency representations such as the windowed Fourier transform and continuous wavelet transform. Other forms of signal analysis include parametric fitting, such as finding the least-squares best-fit.