Siri

Siri (/ˈsɪri/ ^ⓘ SEER-ee) is a digital assistant purchased, developed, and popularized by Apple Inc., which is included in the iOS, iPadOS, watchOS, macOS, Apple TV, audioOS, and visionOS operating systems. It uses voice queries, gesture based control, focus-tracking and a natural-language user interface to answer questions, make recommendations, and perform actions by delegating requests to a set of Internet services. With continued use, it adapts to users' individual language usages, searches, and preferences, returning individualized results.

Siri is a spin-off from a project developed by the SRI International Artificial Intelligence Center. Its speech recognition engine was provided by Nuance Communications, and it uses advanced machine learning technologies to function. Its original American, British, and Australian voice actors recorded their respective voices around 2005, unaware of the recordings' eventual usage. Siri was released as an app for iOS in February 2010. Two months later, Apple acquired it and integrated it into the iPhone 4s at its release on 4 October 2011, removing the separate app from the iOS App Store. Siri has since been an integral part of Apple's products, having been adapted into other hardware devices including newer iPhone models, iPad, iPod Touch, Mac, AirPods, Apple TV, HomePod, and Apple Vision Pro.

Siri supports a wide range of user commands, including performing phone actions, checking basic information, scheduling events and reminders, handling device settings, searching the Internet, navigating areas, finding information on entertainment, and being able to engage with iOS-integrated apps. With the release of iOS 10, in 2016, Apple opened up limited third-party access to Siri, including third-party messaging apps, as well as payments, ride-sharing, and Internet calling apps. With the release of iOS 11, Apple updated Siri's voice and added support for follow-up questions, language translation, and additional third-party actions. iOS 17 and iPadOS 17 enabled users to activate Siri by simply saying "Siri", while the previous command, "Hey Siri", is still supported. Siri was upgraded to using Apple Intelligence on iOS 18, iPadOS 18, and macOS Sequoia, replacing the logo.

Siri's original release on iPhone 4s in October 2011 received mixed reviews. It received praise for its voice recognition and contextual knowledge of user information, including calendar appointments, but was criticized for requiring stiff user commands and having a lack of flexibility. It was also criticized for lacking information on certain nearby places and for its inability to understand certain English accents. During the mid-2010s, a number of media reports said that Siri lacked innovation, particularly against new competing voice assistants. The reports concerned Siri's limited set of features, "bad" voice recognition, and undeveloped service integrations as causing trouble for Apple in the field of artificial intelligence and cloud-based services; the basis for the complaints reportedly due to stifled development, as caused by Apple's prioritization of user privacy and executive power struggles within the company. Its launch was also overshadowed by the death of Steve Jobs, which occurred one day after the launch.

Siri is a spin-out from the Stanford Research Institute's Artificial Intelligence Center and is an offshoot of the US Defense Advanced Research Projects Agency's (DARPA)-funded CALO project. SRI International used the NABC Framework to define the value proposition for Siri. It was co-founded by Dag Kittlaus, Tom Gruber, and Adam Cheyer. Kittlaus named Siri after a co-worker in Norway; the name is a short form of the name Sigrid, from Old Norse Sigríðr, composed of the elements sigr "victory" and fríðr "beautiful".

Siri's speech recognition engine was provided by Nuance Communications, a speech technology company. Neither Apple nor Nuance acknowledged this for years, until Nuance CEO Paul Ricci confirmed it at a 2013 technology conference. The speech recognition system uses sophisticated machine learning techniques, including convolutional neural networks and long short-term memory.

The initial Siri prototype was implemented using the Active platform, a joint project between the Artificial Intelligence Center of SRI International and the Vrai Group at Ecole Polytechnique Fédérale de Lausanne. The Active platform was the focus of a Ph.D. thesis led by Didier Guzzoni, who joined Siri as its chief scientist.

Siri was acquired by Apple Inc. in April 2010 under the direction of Steve Jobs. Apple's first notion of a digital personal assistant appeared in a 1987 concept video, Knowledge Navigator.