The height of the wave is called its amplitude. Sound waves are louder when the amplitude is higher.
Light waves are brighter when the amplitude is higher.
In the animation you can change the amplitude by typing a number between 2 and 90 and then clicking the Amplitude button. Wavelength is the distance between successive peaks. There is a relationship between wavelength and frequency. The shorter the wavelength is, the higher the frequency and vice versa. For visible light, the blue end of the spectrum has the shortest wavelength and the highest frequency.