String theory is a theoretical framework in physics that seeks to unify the four fundamental forces of nature: gravity, electromagnetism, the weak nuclear force, and the strong nuclear force. It posits that the basic building blocks of the universe are not particles but rather tiny, vibrating strings. These strings can exist in multiple dimensions and their vibrations correspond to different particles and interactions. String theory has gained attention for its potential to provide a unified description of the fundamental forces, as well as resolve some of the long-standing issues in theoretical physics, such as the incompatibility between quantum mechanics and general relativity. However, it is still a highly speculative and complex theory that has yet to be experimentally confirmed.