Siri, IOS Intelligent Personal Assistant Answers, IPhone 4S

Siri's primary technical areas focus on a Conversational Interface, Personal Context Awareness, and Service Delegation.
Siri's voice recognition engine is provided by Nuance Communications, a speech technology company.
Siri's actions and answers rely upon a growing ecosystem of partners, including:
• OpenTable, Gayot, CitySearch, BooRah, Yelp, Yahoo Local, ReserveTravel, Localeze for restaurant and business questions and actions;