Volume controls are devices or features that allow users to adjust the loudness of audio output. They can be found on various devices, including televisions, smartphones, and computers. Volume controls can be physical knobs, buttons, or digital sliders in software applications. These controls typically operate on a scale, where turning the knob or sliding the bar increases or decreases the sound level. Some volume controls also include options for mute or balance, which help manage audio output for different speakers or channels, enhancing the overall listening experience.