A toddler meanders unsteadily through the living room, pausing by a sleek black cylinder in the corner. “Alexa,” he says in a high-pitched voice. “Play children music.” The cylinder acknowledges the request, despite the muffled pronunciation, and the music starts.

Alexa, a cloud-based speech recognition software from Amazon and the brain of its black cylindrical loudspeaker Echo, has been a big hit around the world – except for the younger ones, who take it for granted. Children will grow up alongside it, just as Alexa will evolve, as the AI powering it learns to answer more and more questions, and – perhaps – one day even converses freely with people.

But anyone older than 10 will know that it hasn’t always been like that. Speech recognition software has come a long, long way to where we are today. Echo is slimmer than a beer glass, but the first speech recognition machines – developed during the middle of the 20th Century – nearly took up an entire room.