Quantum fields are fundamental entities in physics that describe how particles interact and exist in space and time. According to quantum field theory, every type of particle, such as electrons or photons, corresponds to a specific quantum field. These fields permeate the universe, and particles are seen as excitations or disturbances in their respective fields. In this framework, interactions between particles occur through the exchange of force-carrying particles, known as gauge bosons. For example, the photon mediates the electromagnetic force. Quantum fields provide a comprehensive way to understand the behavior of matter and energy at the smallest scales, bridging the gap between quantum mechanics and relativity.