<mathematics> A technique for expressing a waveform as a weighted sum of sines and cosines.
Computers generally rely on the version known as discrete Fourier transform.
Named after J. B. Joseph Fourier (1768 -- 1830).
See also wavelet, discrete cosine transform.
Try this search on Wikipedia, OneLook, Google
Nearby terms: four-colour glossies « four colour map theorem « four colour theorem « Fourier transform » fourth generation computer » fourth generation language » fourth normal form