Due to double nature of particles in quantum physics some aspects of particle behavior can be best studied by modeling it as a wave. Such wave has limited extension in space and limited duration in time. For study and description it is represented as the superposition of many monochromatic plane waves and is called wave packet. The objective of this activity is to understand how wave packets of limited spatial extent can be constructed from the superposition of plane waves of different amplitudes and wavelengths. The waveform displayed in the Ψ(x) window is the superposition of plane waves with wavelengths between λ ? 1/2Δλ and λ + 1/2 Δλ. With help of floating bands controls you may change values of λ and Δλ and observe the form and characteristics of wave packet.