what is the relationship of card device and sink in linux pulseaudio

In Linux PulseAudio, the relationship between card, device, and sink is as follows:

• Card: A sound card in the system, which represents a physical or virtual audio device. Each card can have one or more devices associated with it.

• Device: A specific audio interface or subsystem within a sound card. It can be an input device (e.g., microphone) or an output device (e.g., speakers). Each device represents a specific audio stream.

• Sink: A destination for audio output. It can be a physical or virtual output device, such as speakers, headphones, or network streams. Sinks receive audio data from one or more devices and play it back.

In simpler terms, a sound card can have multiple devices, and each device can have one or more sinks connected to it. The sinks are responsible for playing the audio data received from the devices