BNC stands for Bayonet Neill-Concelman.
A twist-on connector commonly used for higher-end video systems, used for both analog and serial digital interface video signals.
BNC connector is one type of RF connector used with coaxial cable. It is mainly used in the transmission of radio and television signals. The characteristic impedance of BNC connectors is between 50 ohms or 75 ohms. It is mostly used in CCTV systems in businesses.
lt can carry audio but depending on the equipment you are connecting to, the way the audio signal is embedded may vary between analog and digital.
However, it is rarely seen in consumer electronics today. .