Relevant Products: TVB2 V2, TVB2, TV2 V2, TV5 V2
Audio Return Channel, or ARC, uses a single HDMI connection to send audio from a TV to the soundbar or soundbase. ARC lets you have one connection between your TV and soundbar/soundbase.
This is great for built in TV Apps such as Netflix; as you can bypass the low quality speakers built into the TV. The audio will instead be sent to your soundbar/soundbase for a massive improvement in sound quality.
Another benefit is if you have multiple sources (Blu-ray and cable box) connected to your TV. With ARC, you can connect everything to the TV, and the TV will send audio down an HDMI cable to the sound bar.
Perhaps the biggest benefit is the inclusion of HDMI CEC commands. This allows you to only have to use one remote to turn on everything in your system as well as volume and mute commands.