Nginx ("engine x") 是一个高性能的 HTTP 和 反向代理 服务器，也是一个 IMAP/POP3/SMTP 代理服务器。 Nginx 是由 Igor Sysoev 为俄罗斯访问量第二的 Rambler.ru 站点开发的，它已经在该站点运行超过两年半了。Igor 将源代码以类BSD许可证的形式发布。尽管还是测试版，但是，Nginx 已经因为它的稳定性、丰富的功能集、示例配置文件和低系统资源的消耗而闻名了。

Nginx 可以在大多数 Unix like OS 上编译运行，并有 Windows 移植版。

Changes with nginx 1.4.2

17 Jul 2013

*) Bugfix: the $r->header_in() embedded perl method did not return value of the "Cookie" and "X-Forwarded-For" request header lines; the bug had appeared in 1.3.14.

*) Bugfix: nginx could not be built with the ngx_mail_ssl_module, but without ngx_http_ssl_module; the bug had appeared in 1.3.14.

*) Bugfix: in the "proxy_set_body" directive. Thanks to Lanshun Zhou.

*) Bugfix: the "fail_timeout" parameter of the "server" directive in the "upstream" context might not work if "max_fails" parameter was used; the bug had appeared in 1.3.0.

*) Bugfix: a segmentation fault might occur in a worker process if the "ssl_stapling" directive was used. Thanks to Piotr Sikora.

*) Bugfix: nginx/Windows might stop accepting connections if several worker processes were used.