This interactive WebGL visualization demonstrates the Fourier transform, converting time-domain signals into frequency spectra. It provides both a naive Discrete Fourier Transform (DFT) implementation and a faster Cooley-Tukey Fast Fourier Transform (FFT) via the jsfft library, with support for multiple window functions like Hamming and Hann. The code shows real-time computation of magnitude spectra from audio buffers using sine and cosine lookup tables, with frequency peaks highlighted.