https://www.bleepingcomputer.com/news/microsoft/the-different-types-of-windows-10-updates/

With Windows 10, Microsoft has introduced a new servicing model known as 'Windows as a Service (WaaS)', which delivers an always up-to-date experience with the latest features and security updates.

In order to facilitate this, Microsoft pushes out a variety of monthly updates that fix bugs, compatibility issues, performance enhancements, and security updates. Windows 10 is also updated twice a year with new "Feature Updates" that aim to modify the Windows 10 experience in a significant way.