If you are interested in knowing about how Cortana works in the background, here is a new video for you.
Bart De Smet, a senior software engineer who was involved in developing Rx(Reactive Extensions) spoke to Channel 9 about how Rx is used in Cortana. The Reactive Extensions (Rx) is a library for composing asynchronous and event-based programs using observable sequences and LINQ-style query operators.
As usual, he has a lot of technical details to share and only so much whiteboard real estate. Bart is still deeply engaged with Rx (evolving it, putting it to new uses, making it even more general and capable). How so, you ask?
Well, ask Cortana. She will tell you that, in fact, Rx is one those wonderful things that make her so asynchronously capable and reliable at managing your calendar and the growing list of other personal things that you have her do for you. (I haven’t actually asked Cortana this, so this is an exercise for the reader…)
Source: Channel 9