North American English is a collective term used for the varieties of the English language that are spoken in the United States and Canada. Because of the considerable similarities in pronunciation, vocabulary and accent between American English and Canadian English, the two spoken languages are often grouped together under a single category (Labov, Ash, & Boberg, 2006; Trudgill & Hannah, 2002). North American English is distinguished from the varieties of English that are spoken in the United Kingdom and Commonwealth of Nations countries such as Australia, New Zealand and South Africa, those in the Caribbean and on the Indian subcontinent. Despite the fact that Canadian spellings often (but not always) follow British usage, the collective term "North American English" is sometimes also used to designate the written language of the two countries.
Many terms in North American English are used almost exclusively in the two countries alone, such as "diaper", "gasoline", and "elevator". Although many English speakers from outside North America regard these words as distinctive "Americanisms", they are just as ubiquitous in Canada. Differences between American and Canadian English are somewhat more apparent in the written form, where Canadians retain much, though not all, of the standard British spelling and punctuation (orthography); however, this affects less than one percent of all words regardless of the dialect in the world.
There are a considerable number of different accents within the regions of both the United States and Canada, originally deriving from the accents prevalent in different English and Scots Irish regions and corresponding to settlement patterns of these peoples in the colonies. These were developed and built upon as new waves of immigration, and migration across the North American continent, brought new accents and dialects to new areas, and as these ways of speaking merged and assimilated with the population. It is claimed that despite the centuries of linguistic changes there is still a resemblance between the English East Anglia accents which would have been used by early English settlers in New England, including the Pilgrims, and modern Northeastern United States accents. Similarly, the accents of Newfoundland is similar to Scots while Appalachian dialect retains Scots Irish features.