Discover how any function can be expressed as a sum of sine waves through 27 interactive demonstrations. Draw shapes with rotating circles, visualize audio frequencies, and see Fourier transforms in action.
See also: Complex Analysis for residues and contour integration of Fourier integrals, Real Analysis for convergence of Fourier series, and Differential Equations for solving heat and wave equations by spectral decomposition.
Sine waves, superposition, and the building blocks of Fourier analysis
Decompose any periodic function into sines and cosines
Draw any shape with rotating circles - the magic of complex Fourier series
Convert between time and frequency domains
See sound as waves and frequencies with real-time spectrograms
Low-pass, high-pass, and convolution - shaping signals
Image frequency analysis, edge detection, and compression
Fourier's original application - watch heat diffuse
MP3, JPEG, MRI, and more - Fourier in the real world