[plug] Separate networks on switch

[J Michael Gilks]

Just a quick question.
I have 2 networks at home, eg 192.168.200.* and 192.168.201.*
If I connect hosts from both networks to a switch will they still be able to 
communicate.
I am sure this won't work with a hub, but it would save some wiring if it 
would work with an unmanaged switch.
Can anyone help me out with this please.
My google skills are lacking sometimes and I cannot come up with a string that 
will give me a coherent answer,
Google answers would be good as well, to save up as examples.

Thanks in advance.

Love
Mike.