In electronics and radio, a tuner is a type of receiver subsystem that receives RF transmissions, such as AM or FM broadcasts, and converts the selected carrier frequency into a form suitable for further processing or output, such as to an amplifier or loudspeaker. A tuner is also a standalone home audio product, component, or device called an AM/FM tuner or a stereo tuner that is part of a hi-fi or stereo system, or a TV tuner for television broadcasts. The verb tuning in radio contexts means adjusting the receiver to detect the desired radio signal carrier frequency that a particular radio station uses. Tuners were a major consumer electronics product in the 20th century but in practice are often integrated into other products in the modern day, such as stereo or AV receivers or portable radios.