How is the Azure DevOps Service version determined

Question

Azure DevOps Service has a version number and I want to know how this version is determined? I know that (in this example) 164 is the sprint number, and .1 is a build in the sprint.
However, it's not clear what the "Dev18" stands for? How is it determined and when does it change?

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narikkadan · Answer 1 · Mar 25, 2022

Only the M164 matters in most cases, because sometimes we may need that to determine if you're in one region with the latest update. We can make the confirmation about the relationship:
Dev18<=>TFS 2020
Dev17<=>TFS 2019
Dev16<=>TFS 2018
Dev15<=>TFS 2017
Dev14<=>TFS 2015

It's the major version of TFS, so it won't be changed frequently. I think it will change only when a new TFS version is released. Hope it helps.