In physics, scattering means changing the direction of movement of a particle. The word is commonly used for the scattering of photons and electrons but also used for other particles. Photon scattering is considered one of the phenomena in radiative transfer (along with absorption and emission) and is sometimes equivalent to absorption followed by emission due to the energy gained from the absorption. The word scattering might be used if emission is immediately following the previous absorption, and the "scattering" concept might be stretched to include longer time intervals between if doing so does not affect the analysis. Some types of scattering:
Note that some photon scattering phenomena follows the pattern of classical (wave) electromagnetic radiation theory, whereas some does not, and is only explained by light's quantum nature.
The term scattering is also used regarding the dynamics of planetary systems, e.g., planets redirected from their orbits. The term may be similarly used for interactions between stars in "crowded" regions such as globular clusters and the centers of galaxies.