FFT is an acronym for Fast Fourier Transform. Use this tag for FFT-related questions. Try to also select a specific chip or software tag when possible.

Some articles about the fft for learning more:

http://en.wikipedia.org/wiki/Fft

http://en.wikipedia.org/wiki/Discrete_Fourier_transform

http://www.dspguide.com/ch12.htm

http://www.complextoreal.com/chapters/fft1.pdf

http://www.complextoreal.com/chapters/fft2.pdf

http://www.complextoreal.com/fft3.htm