What is nginx?

Nginx (pronounced “engine‑x”) is a free, open‑source software that works as a web server, reverse proxy, load balancer, and HTTP cache. It’s designed to handle many connections at the same time while using very little memory and CPU.

Let's break it down

  • Web server: It delivers web pages (HTML, images, videos) to visitors’ browsers.
  • Reverse proxy: It sits in front of other servers, receives requests, and forwards them to the right place.
  • Load balancer: It spreads traffic across multiple servers so no single machine gets overloaded.
  • Cache: It stores copies of frequently requested content to serve it faster next time.

Why does it matter?

Because the internet needs to serve millions of users quickly and reliably. Nginx’s ability to handle many simultaneous connections with low resource usage makes websites faster, more stable, and cheaper to run.

Where is it used?

  • Popular websites and services (e.g., Netflix, Dropbox, WordPress.com) use Nginx to serve content.
  • Cloud platforms and hosting providers often include Nginx as a default web server.
  • Companies use it as a front‑end proxy for applications built with Node.js, Python, Ruby, Java, etc.
  • It’s also common in containerized environments (Docker, Kubernetes) for routing traffic.

Good things about it

  • High performance: Handles thousands of connections with minimal memory.
  • Low resource consumption: Runs well on small VPS or even Raspberry Pi.
  • Flexible configuration: Supports virtual hosts, SSL/TLS, URL rewriting, and more.
  • Built‑in load balancing: Simple round‑robin, least‑connections, IP‑hash methods.
  • Active community: Plenty of tutorials, modules, and third‑party extensions.
  • Open source: Free to use, modify, and distribute.

Not-so-good things

  • Configuration syntax can be confusing for beginners compared to some other servers.
  • Limited dynamic module loading in the open‑source version (requires recompiling for new modules).
  • Less feature‑rich for certain use‑cases (e.g., built‑in CGI support) compared to Apache.
  • Debugging can be harder because error logs are less verbose by default.
  • Learning curve for advanced features like stream proxying or complex load‑balancing rules.