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This week on Witness History, the smart speaker Alexa is used by hundreds of millions of people around the world.
But did you know its voice was created by two students in Poland.
After watching old sci fi movies, Wukas and Michal decided they could create a device which sounded less robotic and more like a human.
After spending years developing their own technology, they started winning awards and big companies like Amazon took notice.
Search and subscribe to Witness History wherever you get your podcasts.
These numbers are ridiculous.
It is sort of incredible.
That's incredible.
This is Crowd Science from the BBC World Service, the show that's sparked by your curiosity.
Week in, week out, our inbox is flooded with your questions about life, earth and the universe.
A sort of disembodied head crawling around on its lips.
So I need a magnifying glass and to look for a beard.
You have suffered for your science.
I think we are constantly surprised and delighted by your endless ingenuity.
So many of the questions we get are things that we'd never even have thought to ask.
And every single crowd science has at least one moment that makes us go, wait, what?
I'm Anand Jagatia, and for this program I've asked the whole crowd science team to share some of their favorite moments from the past year that have had their jaws on the floor.
You see that thing beating?
I do indeed.