Active Noise-Cancelling (ANC) is a technology used in headphones and earphones to reduce unwanted ambient sounds. It works by using built-in microphones to pick up external noise and then generating sound waves that are the exact opposite, effectively canceling out the unwanted sounds. This process allows users to enjoy music or podcasts without distractions from their surroundings. ANC is particularly useful in noisy environments, such as airplanes or busy streets, where background noise can be overwhelming. Many modern devices, including Bluetooth headphones and smartphones, incorporate this technology to enhance the listening experience and provide a more immersive sound environment.