Several third party apps have used those APIs to provide virtual desktops, but Windows 10 has made this feature available out-of-the-box in a useful way. The ability to have multiple desktops exists in Windows since Windows 2000 at the API level.
For users of Mac OS X or Linux, this feature is not spectacular or exciting, but for casual PC users who have used Windows only since eternity, it is a step forward. Windows 10 includes the virtual desktops feature, also known as Task View.
Finally, you can give them meaningful names like "Office", "Browsers", etc. Prior to this update, virtual desktops were simply named "Desktop 1", "Desktop 2", and so on. The new option is available starting in Windows 10 build 18963.