# Text-to-speech

> Technology that reads written text aloud in a synthetic voice.

- Level: Basic
- Topics: AI
- URL: https://tidbit.legios.com.ar/text-to-speech/
- In Spanish: [Texto a voz](https://tidbit.legios.com.ar/es/text-to-speech/)

**Text-to-speech**, or TTS, turns written text into spoken audio. It is the voice of your GPS, the screen reader that lets blind people use a phone, the narrator of some audiobooks and the reply of a voice assistant.

Early systems either sounded robotic or glued together tiny recorded snippets of a real person, which gave that choppy, slightly off rhythm. Today's systems are neural networks trained on many hours of recorded speech, and they can sound remarkably natural: pauses, intonation, even a smile in the voice. Developers can tune pronunciation and pacing with a markup language called SSML. On AWS, the service is Amazon Polly.

The same progress has a darker side. Some modern models can imitate a specific person's voice from a short recording, which is useful for someone who is losing their ability to speak, and dangerous in the hands of scammers who fake a relative's voice on the phone. That is why voice cloning features usually require consent from the owner of the voice.

## An analogy

A tireless voice actor who can read anything you hand them, in any of dozens of voices, instantly and at any hour.

## Keep in mind

- Converts written text into spoken audio.
- Powers screen readers, navigation apps and voice assistants.
- Neural TTS sounds far more natural than older systems.
- Voice cloning makes consent and fraud real concerns.

## Go deeper

- [Speech synthesis on Wikipedia](https://en.wikipedia.org/wiki/Speech_synthesis)
- [What is Amazon Polly? (official docs)](https://docs.aws.amazon.com/polly/latest/dg/what-is.html)

## Related terms

- [Web accessibility](https://tidbit.legios.com.ar/web-accessibility/): Making websites and apps usable by everyone, including people with disabilities.
- [Voice assistant](https://tidbit.legios.com.ar/voice-assistant/): Software you talk to out loud that answers back and does small tasks for you.
- [Neural network](https://tidbit.legios.com.ar/neural-network/): A pile of tiny math units that learns patterns from examples.
- [Amazon Polly](https://tidbit.legios.com.ar/amazon-polly/): An AWS service that turns written text into spoken audio.
- [Online scams](https://tidbit.legios.com.ar/online-scams/): Tricks that use messages, sites and apps to get you to hand over money or data.
- [Voice cloning](https://tidbit.legios.com.ar/voice-cloning/): AI that learns to speak in a real person's voice from a short recording.