Magnolia - Magnolia is a digital business platform with a CMS at its core.
Sitecake - Drag and drop CMS for HTML websites. It's flat file CMS so it's pretty fast.
Pulse CMS - A simpler WordPress. The CMS for web professionals.
TYPO3 - TYPO3.com - Infos, SLAs, Extended Support Versions and more
WordPress - WordPress is web software you can use to create a beautiful website or blog. We like to say that WordPress is both free and priceless at the same time.
ClassicPress - The WordPress fork. No Gutenberg. Great future!