A wave is a disturbance that travels through a medium (like water or air) or empty space, transferring energy from one point to another without transferring matter. Think of a crowd doing "the wave" at a stadium. The people (matter) mostly move up and down, but the wave shape (energy) travels all the way around.
Amplitude is the maximum height of the wave from its resting position. A wave with a higher amplitude carries much more energy. This is the difference between a small ripple and a giant tsunami wave.
Frequency is how many full waves pass a point per second. Wavelength is the distance from one peak of a wave to the next. They are inversely related: as frequency goes up, wavelength gets shorter.
The energy ($E$) a wave carries is directly proportional to the square of its amplitude ($A^2$) and the square of its frequency ($f^2$). This means doubling the amplitude makes the energy four times stronger!
The relationship is: $$E \propto A^2 f^2$$
Use the sliders below to see how a wave's properties affect its energy.