Microsoft has had a delivery mechanism called “MSI” which is the windows installer, for installing and updating the components of Microsoft Office for ages. This link has more on MSI.

Starting around Office 2010, we incorporated “Click to run” as an option for updating office.

Office 2019 is EXCLUSIVELY Click to Run.

Office 365 has been delivered by click-to-run primarily since 2013. We still have standalone office, but more and more industry customers are migrating to the cloud, and therefore deploying Office 365.

To get a sense of Office 365, you need to know Microsoft desires to do a more-continuous nonbreaking update model. This article can help explain it

To use a software management solution with Click to Run, check this article out. There is a COM interface you can use!

I hope this helps software vendors who integrate with Office!