Understanding Sinks in Deep Stream Reference app

Hello There
I am looking at deep stream configuration files and the types of groups and their fields. One field properties which I am facing issues in understanding is the sink group.

Any one who can guide me where I can find a bit more comprehensive explanation of the sink group types like fake sink, EGL based windowed sink (nveglglessink) ,Encode + File Save (encoder + muxer + filesink) , Encode + RTSP streaming ,Overlay (Jetson only), Message converter + Message broker


Please take a look at the source code: