Introduction to Nginx

What is Nginx?

Nginx (pronounced engine-x) is a high-performance web server, reverse proxy and load balancer. It handles thousands of concurrent connections on modest hardware because of its event-driven, asynchronous architecture - one worker process serves many requests without a thread per connection.

Why Nginx?

• Speed - static files and proxy traffic are handled extremely efficiently.
• Reverse proxy - sits in front of app servers (Tomcat, Node, PHP-FPM) and forwards requests.
• Load balancing - spreads traffic across several backends.
• TLS termination - handles HTTPS certificates and offloads encryption.
• Caching and gzip - serves cached responses and compressed content.

Nginx vs Apache

Apache uses a process/thread per request (simpler, feature-rich via .htaccess); Nginx is event-driven (better under concurrent load, config is centralized). Many production stacks use Nginx in front and leave historical Apache behind.

Core Vocabulary

• Directive - a config instruction: listen 80;, root /var/www;.
• Context - where directives live: http, server, location, upstream.
• Server block - one virtual host (site).
• Worker - a process serving requests (one per CPU core by default).

Key Points

• Nginx excels at concurrency, proxying, TLS and caching.
• Configuration is centralized and directive-based, not per-folder (.htaccess).
• Understand contexts - directives mean different things in different blocks.