WebRTC (Web Real-Time Communication) is an open-source technology that enables real-time audio, video calls, and data transfer between web browsers and mobile applications through a simple API. The WebRTC connection establishment process involves multiple steps, including signaling server communication, offer/answer exchange, ICE candidate exchange, and establishing a connection. The core components of WebRTC include signaling servers, RTCPeerConnection, Offer/Answer mechanism, session description, and channels for data and media transmission. ICE (Interactive Connectivity Establishment) is a crucial technology in WebRTC for solving network connectivity issues, such as NAT traversal and selecting the best communication path. ICE works by collecting candidates, exchanging them, performing connectivity checks, and selecting the optimal path for communication. Finally, a sample implementation of a signaling server for WebRTC-based peer-to-peer chat is presented.