Apache
Noun · Development
Definitions
Apache typically refers to the Apache HTTP Server, the world's most influential open-source web server. First released in 1995 and maintained by the Apache Software Foundation, it played a central role in the early growth of the World Wide Web and remains widely deployed today. Apache processes HTTP requests and serves web content using a modular architecture, where functionality like URL rewriting (mod_rewrite), authentication (mod_auth), SSL/TLS (mod_ssl), proxying (mod_proxy), and caching can be added or removed through loadable modules. Apache supports multiple processing models (MPMs): prefork uses one process per connection, worker uses threads within processes, and event uses an asynchronous model for better concurrency. Configuration is typically done through httpd.conf files and per-directory .htaccess files, giving administrators granular control over server behavior. Apache supports virtual hosting, allowing a single server to host multiple websites. While Nginx has surpassed Apache in market share for high-concurrency scenarios due to its event-driven architecture, Apache's flexibility, extensive module ecosystem, and compatibility with tools like PHP-FPM and WordPress keep it widely used in shared hosting and enterprise environments.
In plain English: Apache is a software engineering concept that helps developers structure code, run systems, or debug behavior more reliably in real projects.
Example: "We standardized on Apache in this service because the old approach was fragile under load; the new implementation reduced operational surprises and made the codebase easier for the next engineer to reason about."