1. What is WebRTC used for?
WebRTC (Web Real-Time Communication) is an open source project that enables real-time peer-to-peer communications between browsers and other devices without frameworks or plugins.
It used to exchange any kind of media through the web (video, audio, data, etc.) and is now used for real-time gaming, voice and video chat, and for peer-to-peer applications.
Note: Google Meet, Google Hangouts, and Google Duo are all examples of applications that use WebRTC.
2. What is signaling server
Signaling server does not do anything with WebRTC, it just provides a way to exchange messages between two peers. Help to exchange necessary information which is needed to establish a connection.
Note: For signaling we can use WebSocket or even HTTP.