The Loop is PHP code used by WordPress to display posts. Using The Loop, WordPress processes each post to be displayed on the current page, and formats it according to how it matches specified criteria within The Loop tags. Any HTML or PHP code in the Loop will be processed on each post. When WordPress documentation ...

WordPress is open source web software that you can install on your web server to create your website, blog, community or network. WordPress started out as a tool for blogging, but has evolved into a full-fledged Content Management System (CMS), capable of powering websites, networks and communities.