Nginx

Nginx, pronounced "engine-ex", is a web server and reverse proxy server that can also function as a load balancer and HTTP cache. It is designed for high concurrency, low memory usage, and reliability, using an asynchronous event-driven architecture to handle many simultaneous connections with a small thread or process footprint.

Developed by Igor Sysoev, the first public release appeared in 2004 to address the C10k problem. Nginx grew into a popular alternative to traditional monolithic servers. It is released under a BSD-like license, making it free to use and modify. A commercial distribution called Nginx Plus offers additional features and enterprise support. In 2019, F5 Networks acquired Nginx, Inc., and continued development of both the open-source project and commercial offerings under the NGINX brand.

Architecture and features: The core is event-driven and non-blocking, allowing a small number of worker processes to handle many connections. Nginx can serve static content efficiently and proxy or load balance to application servers. It supports multiple load-balancing methods (round-robin, least connections, IP-hash), TLS termination, HTTP/2, WebSocket, and various caching and compression options. It also provides a modular configuration and supports dynamic modules; configuration is centralized in nginx.conf with http, server, and location blocks.

Deployment and usage: Nginx is widely deployed for front-end handling of traffic to back-end services written in various languages. It is common in large, high-traffic sites and cloud-native environments, including containers and orchestration platforms such as Docker and Kubernetes. It runs on major operating systems, including Linux, BSD, Windows, and macOS, and is often used in conjunction with other web servers or application servers.