HTTP/3 is the to-become next generation of the HTTP protocol family. This version is similar to HTTP/2 in features, and is most different than its predecessor primarily by the fact that HTTP/3 will only be done over QUIC.
QUIC is a new reliable transport protocol that could be viewed as a sort of next generation TCP.
HTTP/3 explained is a free and open booklet describing the HTTP/3 and QUIC protocols.
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