This visualization demonstrates the Fast Fourier Transform (FFT) applied to a composite signal of three sine waves at 40, 15, and 25 Hz. It displays the frequency spectrum as a line chart, showing amplitude peaks at the corresponding frequencies, alongside axes labeled "Frequency Peaks of Sine Waves" and "Signal Amplitude." The code generates test data using a custom `sineGenerator`, computes the FFT with algorithms from `DSP.js` and `fourier.js`, and renders the result via D3 scales, line generator, and axes within an SVG canvas.