Hi Nuranar,
American corn always seems to be what we'd describe as maize, whereas corn in Britain can mean any cereal grain, like wheat or barley. Paradoxically corn-on-the-cob is indeed maize too, though off the cob it'd be called sweetcorn.
We don't grow much in the way of maize in the UK - too cold and wet probably.
Meanwhile cobs can be bread rolls, which are baps, but can also be ponies or small horses, or male swans I think!
There are probably dozens of different words for breads and hundreds for cakes, maybe even hundreds and thousands
if you include puddings as well and thats just in English, let alone Welsh, Gaelic, Manx and Cornish.