> 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/en.md).

# English

This book effort was started in March 2018. The plan is to document HTTP/3 and its underlying protocol: QUIC. Why, how they work, protocol details, the implementations and more.

The book is entirely free and is meant to be a collaborative effort involving anyone and everyone who wants to help out.

## Prerequisites

A reader of this book is presumed to have a basic understanding of TCP/IP networking, the fundamentals of HTTP and the web. For further insights and specifics about HTTP/2 we recommend first reading up the details in [http2 explained](https://daniel.haxx.se/http2/).

## Author

This book is created and the work is started by [Daniel Stenberg](https://daniel.haxx.se/). Daniel is the founder and lead developer of [curl](https://curl.haxx.se/), the world's most widely used HTTP client software. Daniel has worked with and on HTTP and internet protocols for over two decades and is the author of [http2 explained](https://daniel.haxx.se/http2/).

## Home

The home page for this book is found at [daniel.haxx.se/http3-explained](https://daniel.haxx.se/http3-explained).

## Help out

If you find mistakes, omissions, errors or blatant lies in this document, please send us a refreshed version of the affected paragraph and we will make amended versions. We will give proper credits to everyone who helps out. I hope to make this document better over time.

Preferably, you submit [errors](https://github.com/bagder/http3-explained/issues) or [pull requests](https://github.com/bagder/http3-explained/pulls) on the book's GitHub page.

## License

This document and all its contents are licensed under the [Creative Commons Attribution 4.0 license](https://creativecommons.org/licenses/by/4.0/).


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