The guitar produces sound through vibrations. When a string is plucked, it vibrates and transfers the vibrations to the bridge and inside the guitar body. These vibrations cause the air inside to vibrate, producing sound. The guitar has evolved over time from its early creation in 1779 by Gaetano Vinaccia to the modern acoustic guitar design by Antonio de Torres in 1850. Les Paul further innovated the guitar by adding microphones, and George Beauchamp created the first electrically amplified guitar in 1936. Mathematics plays a role in the guitar's complex shapes and materials that affect resonance and sound. Equations relate the wavelength and frequency of vibrations as well as the tension and speed of the string's waves.