Parts of the wave diagram
A wave consists of a series of peaks and troughs. Peaks are at the top, or crest, of the wave and troughs are at the bottom (lowest-point) of the wave. The wavelength of a wave is the distance from one point on a wave to the next identical point and is usually measured from peak to peak or trough to trough. The amplitude of the wave is the half-height of the wave, measured from the mid-point of the wave to the peak or the mid-point to the trough. The frequency of a wave is the number of waves that pass a point in one second. The speed of a wave is equal to the frequency of the wave multiplied by the wavelength of the wave.