WordPress is a free and open-source content management system based on PHP and MySQL. Features include a plugin architecture and a template system. I developed hundreds of websites with premium WordPress themes and child themes, for example, I often develop with Avada, Divi theme, Salient, Jupiter, X theme (Xtheme), The7, Bridge, uDesign, Be Theme, Jupiter, Sahifa, Brooklyn, Kallyas, inFocus and many other themes.