How does Facebook M differ from Siri and Google Now?
Facebook Launches M, Its Bold Answer to Siri and Cortana
M is a hybrid. It’s a virtual assistant powered by artificial intelligence as well as a band of Facebook employees, dubbed M trainers, who will make sure that every request is answered.
To try the new service, users will tap a small button at the bottom of the Messenger app to send a note to M, the same way they might message anyone on Facebook. M’s software will decode the natural language, ask followup questions in the message thread, and send updates as the task is completed.