> For the complete documentation index, see [llms.txt](https://http3-explained.haxx.se/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://http3-explained.haxx.se/zh-tw/proc/proc-h2.md).

# 從HTTP/2得到的經驗

HTTP/2 的規範 RFC 7540 發布於 2015 年 5 月，在 QUIC 首次引入 IETF 的前一個月。

HTTP/2 的發布為 HTTP 進化提供了好的經驗。 這一經驗讓大家相信，迭代更新的 HTTP 版本會比從第一版到第二版（ 花費約16年 ）快得多。

使用 HTTP/2，用戶和軟體堆疊習慣了這樣的想法，不再假設 HTTP 是一個序列化的、基於文本的協定。

QUIC 之上 的 HTTP（ HTTP/3 ）建立在 HTTP/2 基礎之上，並遵循許多相同的概念，不過它們從 HTTP 中移走了一些已經被 QUIC 所包含的規範。

HTTP-over-QUIC 於 2018 年 11 月更名為 HTTP/3。


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