Questions for contract editor: Fee and deposit fields

Hi,

I’m using the contract editor (http://contracts.aepps.com/)). I have two questions about the fields in the editor:

  1. There is the deposit field in the contract editor. What the difference between the deposit and amount field? Is the deposit field may be relevant for state channels?

  2. The fee field. As far as I understood it the fee is similarly calculated to the fee in ethereum. You say how much you want to pay per gas and this gets multiplate by how much gas the contract execution actually costs. But why do you need a fee field, what does it do?

Thanks a lot for your help AE community:)