Microsoft is obviously proud of Cortana, its personal digital assistant. It integrated Cortana into Windows 10, Windows Phone and released an app for Apple and Android. However, Cortana wasn't Microsoft's first digital assistant. Remember Clippy?
This was the animated paper clip included in multiple versions of Word that would pop up and try to be helpful. Usually he was just annoying and got in the way, so most people shut him off. Now it looks like Cortana might be headed down the same path.
In an upcoming update to Windows 10 codenamed Redstone, Cortana is going to get a huge upgrade to do more in Windows. It's possible she'll float around the screen, so she can pop up in documents, file folders and other areas to provide assistance.
That assistance could be offering to pull up more information or listing other things you can do in the area. Cortana will also let you more easily control Windows functions like muting notifications. You just have to ask.
Microsoft is very fast to say that Cortana isn't going to be an animated character like Clippy. It will probably just be Cortana's existing expanding circle icon, and it will probably be small.
Cortana could also work across multiple gadgets. Right now, you can use Cortana to reply to missed calls in Android via a text message in Windows. There will probably be much more of that in the future.
Of course, not everyone is happy with Cortana. She does gather a lot of information about you and shares it with Microsoft. Fortunately, you can turn her off if you want.