NGINX is a free Web (or HTTP) server software as well as a reverse proxy. The documentation is available in several languages. It is, as of April 2019, the most widely used web server in the world

NGINX is an asynchronous system as opposed to synchronous servers where each request is handled by a dedicated process. Instead of exploiting a parallel architecture and time multiplexing of tasks by the operating system, NGINX uses state changes to handle multiple connections at the same time; the processing of each request is broken down into many mini-tasks and thus allows for efficient multiplexing between connections. In order to take advantage of multiprocessor computers, several processes can be started. This choice of architecture results in very high performance, but also particularly low load and memory consumption compared to traditional HTTP servers, such as Apache.