CEC stands for Consumer Electronics Control, and it is a feature that allows HDMI devices to be controlled with one remote control. It enables devices connected to your TV through HDMI ports to communicate and control each other. CEC offers convenience by enabling one remote or device to control multiple devices in your multimedia setup. When you try to cast to a CEC supported TV while on a different source input, the source input will automatically switch to the HDMI port where the Chromecast is connected. Certain TVs will also power on (when powered off) when trying to cast to the Chromecast.

Most TVs and devices support HDMI-CEC, but it may be referred to by different branded trade names, so check your devices settings to enable it. Manufacturers often call CEC by different names, including Anynet+ (Samsung), Aquos Link (Sharp), BRAVIA Link and BRAVIA Sync (Sony), HDMI-CEC (Hitachi), CE-Link and Regza Link (Toshiba), SimpLink (LG), HDAVI Control, EZ-Sync, VIERA Link (Panasonic), EasyLink (Philips), and Realink for HDMI (Mitsubishi) .

In summary, CEC is a feature that allows HDMI devices to be controlled with one remote control, and it enables devices connected to your TV through HDMI ports to communicate and control each other. It offers convenience by enabling one remote or device to control multiple devices in your multimedia setup.