Subject: How do magnetic fields work in terms of shape? Also - sparks seen

Are all magnetic fields a closed circular shape?  Is so, does this shape 
have any affect on the way they work? 
While I was in my basement playing with two conserderably strong magnets, 
I observed sparks jumping from one magnet to another. Is this normal 
behavior? One of the magnets were an electromagnet and the other was a 
thick 3  1/2magnet like the type you would find on the back of a 
refridgerator magnet.  This also raised another question, can magnets 
create electricity? 

Thanks for your trouble!

Re: How do magnetic fields work in terms of shape? Also - sparks seen