The following movies show standing waves as the superposition of two sine waves traveling in opposite directions. In each case the fundamental waves are in black and the superposition is shown in blue. Each movie is set up for seamless looping, but you may have to download and play them outside your browser to enable the loop feature.

Pulsed Superposition [66K] The superposition of two truncated sinusoids showing the development of the standing wave as they pass "through" each other.
Classic Standing Wave [63K] The superposition of two continuous sinusoids of identical wavelength, velocity, and amplitude.
Standing Wave Ratio = 7 [63K] The superposition of two continuous sinusoids of identical wavelength and velocity, but with amplitudes in the ratio of 4 to 3 combining to yield a "Standing Wave Ratio" of 7 to 1 (maximum amplitude to minimum amplitude of the superposition.)
Standing Wave Ratio = 3 [66K] The superposition of two continuous sinusoids of identical wavelength and velocity, but with amplitudes in the ratio of 2 to 1 combining to yield a "Standing Wave Ratio" of 3 to 1.
Damped Superposition [49K] Two damped waves propagate in opposite directions. In effect one gets different standing wave ratios at different positions. Energy is transported from each side toward the center of the pattern where the two amplitudes are equal and the wave becomes stationary.