Electromagnetic waves are a type of transverse wave that consist of electric and magnetic fields oscillating in phase, perpendicular to each other and to the direction of propagation. They do not require a medium to propagate and can therefore travel through a vacuum. Electromagnetic waves include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.

Gravitational waves

Gravitational waves are a type of transverse wave that is caused by the acceleration of massive objects. They are ripples in the curvature of spacetime that travel at the speed of light. Gravitational waves were first predicted by Albert Einstein in 1916 as part of his general theory of relativity. They were first directly detected in 2015 by the Laser Interferometer Gravitational-Wave Observatory (LIGO).

Scalar waves

Scalar waves are a type of longitudinal wave that consists of a single scalar field that oscillates in time and space. Scalar waves are not well-understood and their existence is not generally accepted by mainstream science. However, there is some evidence to suggest that scalar waves may exist and may have a variety of applications, such as in energy healing and telecommunications.