The roots of the revolutionary voice assistant can be traced back to 2003 when the US Defense Advanced Research Projects Agency (DARPA) funded the CALO (Cognitive Assistant that Learns and Organizes) project at SRI International12. This ambitious initiative aimed to create an AI capable of understanding and executing voice commands with unprecedented accuracy. In 2007, SRI International researchers Dag Kittlaus, Tom Gruber, and Adam Cheyer spun off Siri, Inc. to commercialize the technology they had developed3. The name "Siri" was chosen by Kittlaus, meaning "beautiful victory" in Old Norse, inspired by a former co-worker in Norway1.

Steve Jobs' first reaction to Siri was one of intense interest and enthusiasm. When Siri Inc. launched their app in early 2010, Jobs personally reached out to the company's CEO, Dag Kittlaus, just three weeks later1. Jobs invited Kittlaus to his home in Cupertino for a three-hour discussion about the future of technology and Siri's potential12.

During this meeting, Jobs expressed his belief that Apple would win the smartphone wars and that Siri could play a crucial role in that victory2. He was particularly impressed with Siri's capabilities, stating, "he felt that we cracked it"2. However, Jobs initially disliked the name "Siri" but ultimately kept it when no better alternatives were found2. Following this meeting, Jobs became relentless in his pursuit of acquiring Siri, reportedly calling Kittlaus "37 days in a row" to finalize the deal3.

In April 2010, Apple acquired Siri, Inc. for a reported $200 million, marking a pivotal moment in the virtual assistant's journey12. This acquisition, made under Steve Jobs' direction, led to Siri's integration into Apple's ecosystem. Initially released as a standalone iOS app in February 2010, Siri was subsequently integrated into the iPhone 4S, which was unveiled on October 4, 201113. Following this announcement, Apple removed the standalone Siri app from the App Store, solidifying its position as an exclusive feature of Apple devices3.

Since its initial release, Siri has undergone significant technological advancements. The speech recognition engine, provided by Nuance Communications, utilizes sophisticated machine learning techniques like convolutional neural networks and long short-term memory1. Language support expanded to include Mandarin Chinese, Japanese, and Russian by 20132. Voice options evolved from the original recordings by Susan Bennett in 2005 to more inclusive and natural-sounding voices, including the introduction of a gender-neutral option nicknamed "Quinn" in February 20223.

Key improvements include the "Hey Siri" wake phrase introduced in 2014, integration with third-party apps via SiriKit in 2015, and enhanced privacy features like on-device processing of user interactions43. These advancements have allowed Siri to better understand natural language, adapt to user preferences, and perform a wider range of tasks while maintaining user privacy.

Revolutionizing human-computer interaction, Siri paved the way for voice-activated personal assistants on smartphones, influencing the development of competitors like Amazon's Alexa and Google Assistant1. Its impact extends beyond Apple's ecosystem, with 87% of iPhone 4S owners using Siri monthly in its early days2. Despite facing criticism for limited features and voice recognition issues in recent years, Siri remains an integral part of Apple's products, integrated into devices ranging from iPhones and iPads to HomePods and the Apple Vision Pro3. This widespread adoption has fundamentally changed how users interact with technology, making it more accessible and intuitive for millions of people worldwide.