ARC is the acronym for Audio Return Channel on your TV or receiver. It is designed to allow a single HDMI cable to carry both video and audio between your TV and Soundbar or audio receiver. This return audio is critical when a program is streamed using a Smart TV app such as Netflix or Hulu. Without the return audio, the sound never reaches your audio system. When working properly, an ARC channel will eliminate multiple cables between your TV and audio system. To work properly, both the TV and audio system must have an ARC input. Be aware even if both your TV and audio system have ARC inputs, as with all new technology, there still maybe be issues. With some TV’s, the ARC input only carries audio from a single input and not others or the ARC input only carries a 2.1 audio signal and not a 5.1 surround sound signal. Consult your TV’s manual to understand how your ARC channel operates. As an FYI, the new Bose Lifestyle 600, Lifestyle 650 consoles and the Bose Soundbar 300 has this ARC feature.