Why does the Earth spin?

[Eighteeteewhy]

The moon doesn't as far as I'm aware?

So why does the earth, and what keeps it spinning?

Do all the other planets spin?


Thanks,

@

[Eighteeteewhy]

Right, so I get that things just spin? Is there any more reason for this, surely it has been investigated further.

People have said that the rotation is slowing down, by how much. How much longer was a day 100 or 1000 or 10,000 or 100,000 years ago?

Perpetual motion has been mentioned, is the earth or even the solar system the biggest perpetual motion machine perhaps?