Personal digital assistants are on the rise (and they want to talk)

Siri, Cortana, Google and Alexa go about their business differently in responding to Ed Baig's questions. NEW YORK-- You may already be on a first-name basis with Siri, Cortana, Google or Alexa, the Fab Four of voice-activated digital assistants. Now that relationship is expanding from one device (typically a smartphone) to many. The major tech companies are putting these digital assistants, powered by artificial intelligence algorithms and activated by voice, into multiple products. And the field is about to get a new name, with the founders of Siri introducing an AI-driven virtual assistant called Viv at the TechCrunch Disrupt conference in New York Monday.