Here's why:

* The relationship: Frequency (f) and wavelength (λ) are inversely proportional. This means that as frequency increases, wavelength decreases, and vice versa. This relationship is described by the following equation:

c = fλ

where:

* c is the speed of light (or the speed of the wave in the medium)

* f is the frequency

* λ is the wavelength

* Examples:

* Gamma rays: Have the highest frequencies and shortest wavelengths in the electromagnetic spectrum.

* X-rays: Also have very high frequencies and short wavelengths.

* Visible light: The color violet has the highest frequency and shortest wavelength within the visible spectrum, while red has the lowest frequency and longest wavelength.

In summary, high frequency waves are characterized by their short wavelengths.