What goes in fish batter as served in traditional British chippys?

Question

and how do they make it?

Answer 1

Self raising flour, salt and water/sparkling water/beer mixed until smooth. Simple as that. You coat the fish in it and drop it in the fryer.

Answer 2

Traditionally it was just there as a protective coating and was discarded before actually eating the fish!

It is made using self raising flour, a pinch of salt, beer (not lager whatever you do! it must be real british beer!) and thats it!