HDMI was created with the goal of simplifying the various audio and video cables into a cable with a smaller connector than DVI to save space in devices built at the time. HDMI is widely used in equipment used for home theater.
In addition to simplifying cabling and reducing connector size, HDMI adds the following features:
- E-DDC (Enhanced Display Data Channel) – Allows audio and video components to recognize each other’s capabilities. For example, the resolution of your television, but it is also used by HDCP (High Bandwidth Digital Content Protection) to protect high-bandwidth digital content and prevent piracy.
- CEC (Consumer Electronics Control) – This communication channel allows connected HDMI devices to control each other. For example the TV will automatically switch to the DVD player when you insert a DVD, or all equipment will go to stand-by if the stereo receiver is turned off. Theoretically CEC also allows you to control all your home theater components using a single remote, but this may vary depending on the compatible equipment.
- ARC (Audio Return Channel) – This feature allows a smart TV to send audio to the stereo receiver without the need for an additional audio cable. For example, if you’re watching Netflix through an app on your TV, but you want the sound to come out of the receiver’s speakers and not the TV’s speakers. Usually only one port is ARC enabled, so make sure you reserve that port for the receiver.
- MHL (Mobile High-Definition Link) – This feature allows you to connect a smartphone or tablet to an HDTV and use the TV’s remote control to control the smartphone or tablet. The MHL enabled port also provides light so your device doesn’t run out of battery power while connected or need a separate charging cable. Usually only one port on the TV is MHL so keep it available for your mobile devices.