The full form of Nginx is Engine-X. It’s used on Computing ,Sofware & Applications in Worldwide

nginx [engine x] is an HTTP and reverse proxy server, a mail proxy server, and a generic TCP/UDP proxy server, originally written by Igor Sysoev. For a long time, it has been running on many heavily loaded Russian sites including Yandex, Mail.Ru, VK, and Rambler. According to Netcraft, nginx served or proxied 23.21% busiest sites in December 2020. Here are some of the success stories: Dropbox, Netflix, Wordpress.com, FastMail.FM.

The sources and documentation are distributed under the 2-clause BSD-like license.

Commercial support is available from Nginx, Inc

Basic HTTP server features

• Serving static and index files, autoindexing; open file descriptor cache;
• Accelerated reverse proxying with caching; load balancing and fault tolerance;
• Accelerated support with caching of FastCGI, uwsgi, SCGI, and memcached servers; load balancing and fault tolerance;
• Modular architecture. Filters include gzipping, byte ranges, chunked responses, XSLT, SSI, and image transformation filter. Multiple SSI inclusions within a single page can be processed in parallel if they are handled by proxied or FastCGI/uwsgi/SCGI servers;
• SSL and TLS SNI support;
• Support for HTTP/2 with weighted and dependency-based prioritization.

Other HTTP server features

• Name-based and IP-based virtual servers;
• Keep-alive and pipelined connections support;
• Access log formats, buffered log writing, fast log rotation, and syslog logging;
• 3xx-5xx error codes redirection;
• The rewrite module: URI changing using regular expressions;
• Executing different functions depending on the client address;
• Access control based on client IP address, by password (HTTP Basic authentication) and by the result of subrequest;
• Validation of HTTP referer;
• The PUT, DELETE, MKCOL, COPY, and MOVE methods;
• FLV and MP4 streaming;
• Response rate limiting;
• Limiting the number of simultaneous connections or requests coming from one address;
• IP-based geolocation;
• A/B testing;
• Request mirroring;
• Embedded Perl;
• njs scripting language.