I think that the point of a thesis like that, is to do some research, and find out for yourself. Asking us seems like rather an 'easy way out'... Perhaps it would be better to do the research first, and then if you find that there are any contentious questions, or conflicting information, we could more usefully comment on that?

On the whole, the differences are tiny, and there are almost no situations in two English speakers, wherever they are from, would not be able to converse nearly perfectly. Among educated people, I think you'd find no difficulty at all. The grammar is exactly the same, with one or two tiny exceptions (in hospital vs. in the hospital) and (England are a good team vs. England is a good team.) there are a handful of vocabulary differences. Regional pronunciation is different between some places. I feel that only a professional linguist could write anything more than a very short paper on the differences.

I don't think anyone would be able to answer your question here, but there are obvious things most everyone notices: Color vs. colour Aluminum vs. aluminium Dependent vs. dependant Pronunciation of schedule TV vs. tele Brits sometimes soften or drop the initial 'h' in a word Brits sometimes sound '-er' as 'uh', like Bostonians And here are hundreds more: https://en.wikipedia.org/wiki/Glossary_of_British_terms_not_widely_used_in_the_United_States There are many dialects in the UK and many colo(u)rful expressions, some of them having ties to the Saxon language. There are also parts of the US in which Scotch-Irish and Germanic linguisitic traditions are preserved, but not likely to the degree you'll find in the UK. Of course, the UK had a colonial history that the US didn't experience in the same way, so there are many words that entered English during this period. Many are used in the US, such as bungalow and jungle, but others are only maintained in British English, like - I don't know, I'm not British, no matter how many episodes of Time Team I've watched. There are fields in which words of a shared origin should be more likely to be found. Also, if you consider the Commonwealth, then there are surely many more differences to be found. During that same period, the US experienced it's own history of expansion, modernization, civil war, and urbanization. Some words, like carpetbagger, only really make sense the US, while others, like scalawag, are more disseminated. In the US you hear a lot of slang and bad grammar. We've probably traded in a lot of the scholar's Latin and French words, too, when it comes to common usage. At one time, though, some Brits taught American English, since it was considered a neutral standard. Sorry I don't have any resources to share, but Wikipedia is probably a good place to begin to get an idea of the differences.

I have a question I personally would like answered! Is there a way to measure the difference between two versions of a language? If so, how big is the difference between "U.S." and "British" English, compared to the regional differences within either country? For example, let's pretend that the "distance" between U.S. English, as used for example on National Public Radio's "Morning Edition," and British English, as used on BBC World Service, is 100 lexes. What's the distance between Maine English and Alabama English? Between Edinburgh English and Liverpool English? I'd bet they are bigger. A lot of the distinction between the two is just an accident of history--and Noah Webster's entrepreneurship in deciding to compile "An American Dictionary of the English Language." A point that I think often gets missed in discussions of the two is that there are very few British usages that you do not hear in the United States. It's just that they are less frequent. Where I live, the people who've grown up here say pronounce the word "laughed" like "lahh-ft," for example. There are exceptions, mostly having to do with vocabulary--a U.S. native might not understand a British native referring to the "boot" of a car. But a Boston speaker might not understand a New Orleans native referring to a "neutral ground" in the middle of a city street.

It largely depends on what forms of American and British English that you are referring to... Both countries have a huge range in different dialects, so it depends whether you're only going to focus on the 'official' English taught in books, or if you're going to focus on the language as it is actually used. For example, Scots English is very different from the English spoken in Texas, yet also from the English spoken in South London. Both may be considerably different from the English spoken yet again in Cardiff.