Photons are light.
These particles are bundles of energy (quanta) of a particular kind of field.
There is one kind of field for every type of elementary particle.
For instance, there is an electromagnetic field whose quanta are photons.[1]
The force carrier particles that mediate the electromagnetic, weak, and strong interactions are called gauge bosons.
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Gravity is not a part of the Standard Model, but it is thought that there may be particles called gravitons which are the excitations of gravitational waves.
The status of this particle is still tentative, because the theory is incomplete and because the interactions of single gravitons may be too weak to be detected.[2]