What sets the Windows Phone apart from competiting smartphones is Cortana, Microsoft's digital assistant that reminds of Google Now and Apple's Siri. Now the company is unifying the experience between all of its products by incorporating the "Halo"-inspired voice in Windows 10 for the desktop.

When Cortana greets with "Hello. What can I do for you?" on your desktop computer, you can use her to make Skype calls, add appointments to your calendar and search everything from the Internet to your computer files, reports Engadget. The Halo-inspired AI assistant will also perform tasks based on natural language commands like "search my email for party invitation."

Cortana's intelligence will be part of Microsoft's replacement to Internet Explorer known as Project Spartan. For example, if you have a flight scheduled, Cortana will update you on the flight status. If you are looking at a restaurant website, Cortana will chime in to offer driving directions, links to reviews and more.

According to Slash Gear, Joe Belfiore, corporate Vice President of the Operating Systems Group at Microsoft, demonstrated using Cortana with Windows 10 onstage Wednesday, showing how Cortana could dictate a message, set a reminder, recite weather conditions, and predict the Super Bowl. The intelligent personal assistant can perform these tasks even with other applications in use, which Belfiore says should allow more efficient multitasking.

"Show me PowerPoint slides about the charity auction," Belfiore told Cortana on the desktop before it obliged.

Cortana desktop comes with  a couple of hew features: her speech recognition cleverly interprets "hashtag" as the "#" symbol, and, although it is unclear when this feature was added, Cortana can now do impressions upon command, Windows Central reports. Plus, users can ask Cortana to "do an impression" and listen to her speak in Yoda's voice, among others.

The database behind Cortana has a Bing-powered knowledge base, which is expanded by learning from users' searches and behavior. The information that Cortana collects about you is stored in the "Notebook." Users can open the Notebook to review what she knows about you.

Belfiore says the rollout of Windows 10 in the U.S. and abroad will be gradual over the coming months.

Microsoft is allowing a Windows 10 preview starting in February-a first. Another first for the company is distributing Windows 10 free on any device for the first year to help adoption rates. The actual release date is unspecified.