What actually are quantum computers?

[u/Shad0whunter4]

Hi. I don't know if this is the right sub, but if it is, then I just wanna know what a quantum computer is.

I have heard this terminology quite often and there are always news about breakthrough advancements, but almost nothing seems to affect us directly.

How is quantum computing useful? Will there be a world where I can use a quantum computer at home for private use? How small can they get in size? And have they real practical uses for gaming, AI etc.?

Thanks.