Extended techniques in music refer to unconventional methods of sound production that go beyond traditional playing techniques. These methods can be applied to various instruments, including strings, woodwinds, and brass, allowing musicians to create unique textures and timbres. Examples include multiphonics, where a player produces multiple pitches simultaneously, and extended bowing techniques on string instruments. Composers like John Cage and George Crumb have popularized the use of extended techniques in their works, encouraging performers to explore new sonic possibilities. This approach challenges the boundaries of music, inviting both musicians and listeners to experience sound in innovative ways.