WordPress hosting is designed specifically as a form of web hosting for WordPress websites, via WordPress.com and WordPress.org. It's platform-specific hosting optimized for WordPress sites, where as other types of web hosting are designed for use with any type of website.
When it comes to managed vs unmanaged hosting, WordPress hosting mainly offers managed hosting, meaning that providers take charge of updates, advanced tasks, and administration of your site, leaving you to focus on what's important to you.