With Windows 10, Microsoft has slowly been working towards a more streamlined way of sending updates to users (when it's not forcing them down your throat). To this end, by February 2019, "express" patches will be the dominant update method.
As Microsoft's Mike Benson explains, the company has three ways of providing patches for Windows 10 — full, express and delta:
- Full updates have all the necessary components and files that have changed since the last feature update. We refer to this as the latest cumulative update, or LCU. It can quickly grow to a little over 1 GB in size, but typically stays that size for the lifetime of that supported version of Windows 10.
- Express updates generate differential downloads for every component in the full update based on several historical bases ... A device leveraging express updates will use network protocol to determine optimal differentials, then download only what is needed, which is typically around 150-200 MB in size each month. Ultimately, the more up to date a device is, the smaller the size of the differential download.
- Delta updates include only the components that changed in the most recent quality update. Delta updates will only install if a device already has the previous month’s update installed ... Delta updates include the full component (not just the individual files) that changed. As a result, they are larger than express updates, often around 300-500 MB in size.
Benson goes on to say that, while express updates are already offered to users who connect via Windows update, delta updates have continued "to give companies and third-party update management tools time to implement support for express updates".
However, this will change early next year:
Now that express update support for third-party update managers has been available for over a year, we plan to stop shipping delta updates. Beginning February 12, 2019 Microsoft will end its practice of creating delta updates for all versions of Windows 10.
Express updates are much smaller in size and simplifying the cumulative options available will reduce complexity for IT administrators.
Something to keep in mind if you're in the habit of handling the update process manually.
Windows has been knocking around in some form or another for a grand total of 32 years now, and in that time it's amassed a lot of features - not just the newest bells and whistles but long-standing features you might have forgotten about or never even discovered in the first place.
Windows 10 quality updates explained & the end of delta updates [Microsoft, via gHacks]