A photon is a tiny object that carries light or other forms of electromagnetic radiation. Photons can be thought of as small “packages” of energy that travel at the speed of light.
Photons have special properties: they sometimes behave like particles and sometimes like waves, depending on how they are observed. This property is called wave-particle duality.
Photons are all around us: they enable us to see, allow plants to photosynthesize, make lasers work, and enable light bulbs and LEDs to produce light. In quantum physics, photons are also used to transmit quantum information, for example in quantum communication or quantum computers.