WordPress is an open-source content management system that enables users to create and maintain websites without needing to code from scratch. It's known for its ease of use, flexibility, and a wide range of themes and plugins that allow for extensive customization. WordPress can be used for a variety of websites, from blogs and personal sites to complex business and e-commerce sites. Its user-friendly interface, robust community, and scalability make it a popular choice for both beginners and professional web developers.