When it comes to the English language, the Americans and Britons seem to behave like children who just want to annoy each another. They can’t agree on “ice” or “iced”. Or how to spell certain words.
And they definitely can’t agree on punctuation. For example, the Americans use two quotation marks to quote someone, but the Brits only use ones. The Americans also place the comma inside the quotation marks, while the Britons place it outside. (Long sigh…)
If it doesn’t make sense (as I’m sure it doesn’t), just take a look at the attached illustration and find the differences