A Content Management System (CMS) is software that helps users create, manage, and modify content on a website without the need for specialized technical knowledge. WordPress is by far the most popular CMS, known for its flexibility, vast plugin ecosystem, and user-friendliness, making it suitable for blogs, business sites, and e-commerce. Joomla and Drupal are other robust open-source options, often favored for more complex or enterprise-level websites due to their advanced features and security. Shopify and WooCommerce are specialized CMS platforms for e-commerce, offering tools specifically designed for online stores. Choosing the right CMS depends on your project's scale, required functionalities, budget, and your team's technical comfort level. A good CMS empowers you to keep your website content fresh and relevant.