Over the past three decades, HTTP has been the foundation of the internet, allowing us to browse, download, and stream online. However, the TCP protocol that HTTP relies on has limitations that result in less responsive web applications. To overcome these downsides, Google introduced QUIC, a game-changing transport protocol that has gained widespread adoption, especially among tech giants like Google and Facebook. QUIC is highly performant compared to TCP, offering reduced latency, multiplexing, improved security, and connection migration. HTTP/3, which uses QUIC at the transport level, is becoming the standard for internet communication and is expected to overtake HTTP/2.
https://engineeringatscale.substack.com/p/how-quic-is-displacing-tcp-for-speed