Voice assistant: how Gemini, Siri and Alexa work

A voice assistant is a program that understands spoken commands and carries them out: it sets alarms, makes calls, looks things up and controls your smart home. The best known are Google Gemini (formerly Google Assistant), Siri, Alexa and Bixby.

From simple commands to real conversation

In plain words

Voice control used to be like a trained parrot: it understood a few exact phrases - "call Mum", "alarm for seven". A modern assistant built on a language model is like an attentive helper: you can speak in your own words, ask follow-up questions and even ask it to explain something complicated.

How it works

The phone listens locally for the wake phrase ("Hey Google", "Hey Siri").
After that it records your command and recognises the speech.
The system works out your intent: a call, a reminder, a question.
It performs the action or builds an answer - on the device or in the cloud.
Speech synthesis reads the answer aloud.

Where voice assistants work

Where you'll see it

In phones (Gemini on Android, Siri on iPhone, Bixby on Samsung), watches, smart speakers, TVs and cars (Android Auto, CarPlay). Support for different languages varies between assistants, so it is worth checking.

Does it matter when buying

It is handy while driving, cooking or wearing earbuds. Check whether the assistant supports your language and which features work in your country. And set up privacy: you can review and delete your voice request history.

Myths

Myth: The assistant records everything I say all the time. Reality: It only listens for the wake phrase locally; recordings after that can be reviewed in settings.
Myth: Voice assistants only understand English. Reality: The leading assistants understand many languages, though features may differ.

FAQ

How do I turn off the voice assistant?

In settings, turn off wake-phrase detection.

Does the assistant work without internet?

Basic commands do on some phones; complex ones need internet.

What have AI models changed?

Assistants now understand natural language and can hold a conversation.