A Content Management System (CMS) is software that allows the creation, editing, and management of digital content. Today, CMS systems are essential tools for webmasters, marketers, bloggers, and digital agencies, as they simplify website management without the need for deep programming knowledge. Below is an overview of 20 popular CMS systems widely used around the globe.

1. Wordpress WordPress is a free and open-source CMS widely used for creating blogs, corporate websites, and e-commerce. With a large number of plugins and themes, it offers a high degree of customizability.

2. Joomla! Joomla! is another popular open-source CMS known for its flexibility and a broad range of features, including advanced user management and extensive support for multilingual content.

3. Drupal Drupal is suitable for more complex web projects and communities, offering extensive customization options and powerful content and user management tools.

4. Magento Magento is an e-commerce-focused CMS providing rich options for managing online stores, including product catalogs, marketing tools, and payment integrations.

5. Shopify Shopify is a popular e-commerce platform allowing easy creation of online stores without programming knowledge.

6. Wix Wix is a cloud-based web builder that enables users to easily create and manage websites using a drag-and-drop interface.

7. Squarespace Squarespace is another website creation platform with an emphasis on design, offering a wide range of templates and tools for creating professional-looking sites.

8. TYPO3 TYPO3 is an enterprise-level open-source CMS suitable for large organizations and corporations needing extensive and flexible web presentations.

9. PrestaShop PrestaShop is another open-source e-commerce platform providing everything needed to start and manage online sales.

10. Weebly Weebly is a web-building platform with an intuitive drag-and-drop interface, suitable for smaller web projects and personal sites.

11. OpenCart OpenCart is a free e-commerce platform offering rich product and order management options, as well as support for multilingual sites.

12. Zen Cart Zen Cart is a user-friendly open-source e-commerce management system focused on vendors seeking easy implementation and customization.

13. Umbraco Umbraco is a CMS based on Microsoft .NET technology, known for its flexibility and powerful content management tools.

14. BigCommerce BigCommerce is a SaaS e-commerce platform offering solutions for growing and managing online stores with extensive integration options.

15. Concrete5 Concrete5 is an open-source CMS that allows easy content and website management thanks to its intuitive interface and a range of available add-ons.

16. MODX MODX is a CMS and framework for developers wanting full control over the appearance and functionality of their website without restrictions.

17. SilverStripe SilverStripe is a PHP-based CMS and framework known for its flexibility and powerful developer tools.

18. Kentico Kentico is an integrated marketing platform combining content management, e-commerce, online marketing, and intranet on one platform.

19. DotNetNuke (DNN) DotNetNuke is a web management platform based on .NET, offering a wide range of features for enterprise clients.

20. Sitecore Sitecore is a powerful digital content management and marketing platform offering integration with analytics, marketing automation, and e-commerce.

This list represents a wide range of CMS systems catering to different needs and target groups, from simple solutions for personal blogs to complex platforms for large corporations. Choosing the right CMS is key to a successful digital project, so it's important to consider the specific requirements of your project when selecting a CMS.