Al has a point. Recently, while installing a new version of DNS, the English choices were: US, CA, UK, OZ - NZ, Indian and Southeast Asia and all of the above.
But, generally, native English speakers tend to understand each other fairly well (unless the speaker is from Manchester).
My father was from Oldham, which is just east of Manchester, so no problem.
@geezer I would've of mentioned a few others before Manchester, like Newcastle or Liverpool!
From Manchester myself but lived in London most of my life and never hear to much of a strong difference compared to places like Newcastle.
I shared a kitchen with guys from Man, Leeds, Branford and Sheffield. English teachers they were. They knocked my English at every chance but luckily their students affected American accents. :-)