The waves with the shortest wavelengths and highest energy in the electromagnetic spectrum are gamma rays.

Here's why:

* Electromagnetic Spectrum: The electromagnetic spectrum is a range of all types of electromagnetic radiation, arranged by their wavelengths and frequencies.

* Wavelength and Energy: Wavelength and energy are inversely proportional. This means that shorter wavelengths correspond to higher energy levels.

* Gamma Rays: Gamma rays have the shortest wavelengths (less than 0.01 nanometers) and the highest frequencies in the electromagnetic spectrum. This means they carry the most energy.

Here's a quick rundown of the electromagnetic spectrum from longest wavelength (lowest energy) to shortest wavelength (highest energy):

* Radio waves

* Microwaves

* Infrared radiation

* Visible light

* Ultraviolet radiation

* X-rays

* Gamma rays