The electroweak theory is a physical theory that unifies two of the four fundamental forces in the universe – electromagnetism and the weak nuclear force. It was developed in the 1970s and forms an integral part of the Standard Model of particle physics. The theory postulates that the electromagnetic force and weak nuclear force are different manifestations of a single unified force at high energies. The electroweak theory correctly predicted the existence of the W and Z bosons, which mediate the weak nuclear force, and has been confirmed through various experimental observations, including the discovery of the Higgs boson in 2012. Electroweak theory plays a crucial role in our understanding of the fundamental interactions between particles and is essential for describing various processes in particle physics, such as particle decays and interactions in high-energy collider experiments.