Some people have been surprised to learn that Microsoft is utilizing the internet connections of Windows 10 users to deliver Windows Updates to others. But this is far from being the end of it. Cortana also gives cause for concern, and then there is the issue of Microsoft Edge, and ads in apps. Is this a price you're willing to pay?
Windows 10 is more closely tied to a Microsoft account than any previous version of the OS. This allows Microsoft to assign an ID number to users that can then be used to track them across different devices, services, and apps. This in turn can be used to deliver closely targeted ads to people. Microsoft has been pushing the mobile first, cloud first philosophy for some time now, and it becomes clear with Windows 10 that the love of the cloud is as much to do with the ability it gives Microsoft to gather useful data as it is about convenience for users.
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