WordPress is a popular open-source content management system (CMS) written in PHP. It is used to create and manage websites, blogs, and web applications. WordPress is known for its ease of use and versatility, making it a popular choice for both novice and experienced users. It has a large community of developers who create plugins and themes, which can be used to add functionality and customize the appearance of a website. It’s a widely used platform and it’s free, it’s used by millions of websites.