Light exhibits characteristics of both particles and waves, and its nature is best described by the theory of quantum electrodynamics (QED). According to QED, light consists of discrete packets of energy called photons, which are the particles associated with electromagnetic radiation. These photons exhibit wave-like properties when considered in aggregate.
The wave-particle duality of light means that it can exhibit wave-like behavior, such as interference and diffraction, as well as particle-like behavior, such as the ability to transfer discrete packets of energy and interact with matter in a particle-like manner. The exact nature of light depends on the experimental setup and the manner in which it is observed or measured.
In certain experiments, light behaves more like a wave, showing interference patterns when passing through slits or diffracting around obstacles. In other experiments, it behaves more like a particle, as in the photoelectric effect, where photons transfer their energy to electrons, causing them to be ejected from a material.
Therefore, it is most accurate to say that light possesses both wave and particle characteristics, and its behavior is determined by the specific experimental context in which it is observed.