The project was prompted by an internal hackathon where accessibility engineers Laura D'Aquila and Abigail Klein noticed that it was difficult for the hearing impaired to follow some presentations.

Automatic captioning will be available in Slides this week for users around the world in US English. While it's unclear how accurate the system will be in practice (YouTube's live captions aren't always on the mark), it should be a vital tool for making presentations more accessible. Google adds that it could even be helpful for people without hearing issues, since you could hold a presentation in a noisy hall without having to shout.