What do Active Record parallel queries do?

[eluser]jtotheb[/eluser]
In the wiki there is "Active Record parallel queries" and i'm trying to work out what it does.

I'll be quite honest and say that i don't really understand.

Does it mean that if i have a query with say 5 where statements, i can split that query up into 5, run them all at once, where they will run quicker? then come out with one result?

I tried reading about it on the internet but it was confusing!