The plan to put Cortana on machines running software from rivals such as Apple and Google, as well as the Einstein project, have not been reported. Cortana is the name of an artificial intelligence character in the video game series "Halo."
They represent a new front in CEO Satya Nadella's battle to sell Microsoft software on any device or platform, rather than trying to force customers to use Windows. Success on rivals' platforms could create new markets and greater relevance for the company best known for its decades-old operating system.
The concept of 'artificial intelligence' is broad, and mobile phones and computers already show dexterity with spoken language and sifting through emails for data, for instance.
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Still, Microsoft believes its work on speech recognition, search and machine learning will let it transform its digital assistant into the first intelligent 'agent' which anticipates users needs. By comparison, Siri is advertised mostly as responding to requests. Google's mobile app, which doesn't have a name like Siri or Cortana, already offers some limited predictive information 'cards' based on what it thinks the user wants to know.
Microsoft has tried to create digital assistants before, without success. Microsoft Bob, released in 1995, was supposed to make using a computer easy, but ended up being the butt of jokes. The Office Assistant nicknamed 'Clippy' suffered a similar fate a few years later.
"We're defining the competitive landscape... of who can provide the most supportive services that make life easier, keep track of things, that complement human memory in a way that helps us get things done," said Horvitz.
Outside his door stands "The Assistant," a monitor showing a woman's face that can converse with visitors, has access to Horvitz's calendar and can book meetings.
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On his desktop, Horvitz runs 'Lifebrowser,' a program that stores everything from appointments to photos and uses machine learning to identify the important moments. A keyword search for his university professor instantly brings up photos and video from the last time they met.