Cortana knows you, and your voice. Just say what you need, like "Hey, Cortana. How do I get to the mall?" In an instant, Cortana is giving you directions.
Windows 10 learns to identify your voice, but also the way you type, and your handwriting. Microsoft, like a lot of other tech companies, is using what it learns about you to customize your experience.
But Windows 10's smarts come with a price. For you, that price is your privacy. In fact, when you look closer at Microsoft's description of Windows 10 features, like learning your style of speaking and writing, you'll find red flags, like, "Some of this data ... is sent to Microsoft."
However, you don't need to be alarmed. We've told you how to customize your privacy settings during the Windows 10 installation and, now, there's an easy way to change your settings after you've installed Windows 10.