WordPress is a content management system (CMS) that allows you to host and build websites. WordPress contains plugin architecture and a template system, so you can customize any website to fit your business, blog, portfolio, or online store.
On a slightly more technical level, WordPress is an open-source content management system licensed under GPLv2, which means that anyone can use or modify the WordPress software for free. A content management system is basically a tool that makes it easy to manage important aspects of your website – like content – without needing to know anything about programming.
The end result is that WordPress makes building a website accessible to anyone – even people who aren’t developers.