The function similar to “Call on Hold”, but in this case it is used during the video conference, by pressing the button, the video conference puts on hold mode.
In the past, when you call an office building or business, you would either be transferred to the department you want to talk to, or given their extension number. This extension is usually a 2-3 digit code that when dialed, transfers you automatically to the particular person or department you want to speak with. The reason why this code works is because it is programmed into a PBX system.