Glossary · Web Development

CMS (Content Management System)

A CMS is software that lets people create, edit and publish website content through an admin interface without writing code for every change.

Updated October 6, 2026

A CMS (content management system) is an application that stores content and templates and lets non-developers create, edit, organize and publish web pages. WordPress, Drupal and Joomla are well-known examples.

Why it matters

A CMS lets marketing and editorial teams work independently of developers. It also adds responsibilities: the platform, themes and plugins need updates, and outdated installs are a common target for attacks. Performance depends on hosting, caching and how many plugins run on each page.

Example

With a traditional CMS, a request for /about triggers this flow: the web server runs PHP, the CMS loads the page content from a database, combines it with the theme template and returns HTML. Caching can skip steps two and three for repeat visitors.

Common mistakes

  • Never updating the core, themes and plugins.
  • Installing many plugins that overlap and slow every page.
  • Skipping backups, then having no recovery path after a failed update.

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