High Quality Content by WIKIPEDIA articles! In mathematics, a wavelet series is a representation of a square-integrable (real- or complex-valued) function by a certain orthonormal series generated by a wavelet. THis article provides a formal, mathematical definition of an orthonormal wavelet and of the integral wavelet transform. A Wavelet is a wave-like oscillation with an amplitude that starts out at zero, increases, and then decreases back to zero. IT can typically be visualized as a "brief oscillation" like one might see recorded by a seismograph or heart monitor. GEnerally, wavelets are purposefully crafted to have specific properties that make them useful for signal processing. WAvelets can be combined, using a "shift, multiply and sum" technique called convolution, with portions of an unknown signal to extract information from the unknown signal.