Also the pronunciation is somewhat different between American and British English, two people may say the same exact sentence, but due to the accent it may sound quite different. There are many very different accents in English (from different English-speaking countries) such as British, Irish, Australian, American (and also different accents from different parts of the country), etc. Somebody from Canada for example may have a difficult time understanding someone with a heavy Irish accent (although I love the Irish accent, it's beautiful).

Also the spelling is sometimes different. For example: British spelling : "colour" American spelling: "color" If you have a spell-checker in a program in your computer, it may give you an option to choose which English you prefer, British or American spelling.

The two languages are quite similar. Of course, each has many vocabulary words that do not exist or have another meaning in the other, however, fundamentally there is little difference between the two.

Thank you very much.