A Brief History of Voice Recognition Technology


Voice recognition technology has come a long way since the first experimental decades of the 1910s to 1980s. In this blog post, we will take a look at the key milestones and breakthroughs that have led to the development of the voice recognition technology we know today.

Experimental Decades: 1910s-1980s

Radio Rex: The First Voice Activated Toy

In 1922, the first voice-activated toy, Radio Rex, was released. It was a wooden toy in the shape of a dog that would come out of its house when its name was called.

Audrey: The Automatic Digit Recognition Machine

In 1952, Bell Labs presented Audrey, an Automatic Digit Recognition machine. It was a complex machine that could recognize the fundamental units of speech, phonemes. However, it was limited to accurate recognition of digits spoken by designated talkers and was not widely adopted as push-button dialing was cheaper and faster.

The IBM Shoebox: A Voice-Activated Calculator

In 1962, IBM presented the Shoebox, a voice-activated calculator. This early computer was able to recognize 16 spoken words and the digits 0 to 9.

ELIZA: The First Chatbot

In the 1960s, MIT professor Joseph Weizenbaum developed the first natural language processing computer program, or chatbot, named ELIZA. It used pattern matching and substitution methodology to simulate conversation, giving an illusion of understanding on the part of the program.

The ELIZA Effect

Weizenbaum's own secretary reportedly asked him to leave the room so that she and ELIZA could have a real conversation. This gave name to the ELIZA effect, the tendency to unconsciously assume computer behaviors are analogous to human behaviors, a phenomenon present in human interactions with virtual assistants.

Harpy: The First Voice Recognition Program with a Vocabulary of 1000 Words

In the 1970s, the Carnegie Mellon University, with substantial support from the United States Department of Defense, developed "Harpy", a voice recognition program with a vocabulary of 1000 words. It could understand sentences and process speech that followed pre-programmed vocabulary, pronunciation, and grammar structures.

Tangora: The Voice Recognizing Typewriter

In 1986, IBM introduced an upgrade of the Shoebox, named Tangora. It was a voice recognizing typewriter with a vocabulary of 20,000 words and used prediction to decide the most likely result based on what was said in the past.

Birth of Smart Virtual Assistants: 1990s-Present

In the 1990s, digital speech recognition technology became a feature of the personal computer with IBM, Philips, and Lernout & Hauspie fighting for customers. The market launch of the first smartphone IBM Simon in 1994 laid the foundation for smart virtual assistants as we know them today.


Voice recognition technology has come a long way since its experimental decades. From the first voice-activated toy Radio Rex to the sophisticated smart virtual assistants of today, the development of voice recognition technology has been a constant evolution. It is exciting to think about what the future holds for this technology and how it will continue to shape the way we interact with machines.