WordPress is an open-source piece of software, which users can download and use to build websites and web apps. WordPress allows you to create a website without code, and also allows developers to extend its functionality.
The software, its plugins and its themes — with which site owners can use to control the style of their website — have been continually maintained since 2003. Because WordPress is open-source, there is no license fee to pay: the downloadable version of the software is free to use.
WordPress is currently in use by over 60% of all websites which use content management systems; that’s over 40% of all websites. (Statistic: W3Techs.)
Downloadable version
The downloadable version of WordPress is managed through the website WordPress.org and is programmed and maintained by volunteers across the world. This is the version to use if you want to have full control over your website, or if you’re working with a freelancer or web agency.
Hosted version (subscription)
WordPress.com was launched in 2005 as an alternative, hosted solution which allows users to create websites without downloading the software. This service is a private commercial enterprise run by Automattic and operates outside the open-source community. However, many of the developers at Automattic use their experience with the hosted solution to contribute back to the onward development of the downloadable software.