Canada has its own political, cultural, historical, and geographical realities and has its own words to describe these realities. It has two official languages, English and French, but in the 2001 census 18% of the population reported having a mother tongue, other than one of the official languages, Chinese being the third most common mother tongue. Canadian English is spoken as a first or second language by over 25 million people. Most of the Canadians who speak French live in the province of Quebec although forty percent of the population of the province of New Brunswick is also francophone. Canada was founded as a union of British colonies, some of which had earlier been under French control. It is a federal dominion with ten provinces and three territories obtained its sovereignty from the United Kingdom in a process beginning in 1867. Canada defines itself as a bilingual and multicultural nation.

The English vocabulary used does not differ enormously from the vocabulary used in other parts of the world, but some words have different connotations in different English speaking countries. The bulk of the words used are common to all English speakers, but there are, a number of words that are peculiar to Canada. Canadian English spelling is a mixture of American, British , and unique Canadianisms. Canadian vocabulary is similar to American English, but with key differences and local variations. Generally speaking, there are no grammatical features that are distinctly Canadian. There are, however, slight differences between American English and British English, and since Canadians are influenced by both, Canadian English is a mixture of both American and British features. In general, Canadian pronunciation is almost identical to American pronunciation, but there are regional differences.

Canadian English includes words borrowed from other languages which do not appear in other varieties of English. The country's name comes from the Iroquoian word Kanata meaning "community". Most of these borrowed words refer to features in the flora, fauna, geography and topography. The native Aboriginal peoples, the British and French settlers, more recent arrivals and occupations in the different regions have all contributed to making Canadian English unique.

Other words have different meanings in Canada, the United States and Britain.

Examples include:

In general, Canadian pronunciation is almost identical to American pronunciation, especially in Ontario. In Nova Scotia, New Brunswick and Price Edward Island, there is a strong Scottish influence and in the Ottawa Valley there is an Irish influence. The pronunciation of people living near, or working with French-Canadians is greatly influenced by French and the island of Newfoundland has its own distinctive English dialect.

The most famous difference between Canadian and American pronunciation is the ou sound in words like house and out, which sound to American ears like hoose and oot. (Some say the words sound more like hoase and oat). Canadians also tend to pronounce cot the same as caught and collar the same as caller. Keen ears will hear a Canadian distinction in certain vowels: the i comes out differently in knife and in knives, in bite and in bide, and in price and in prizes. Many Canadians also will turn t sounds into d sounds, so the name of the capital sounds like "Oddawa."

The main difference between Canadian English and that of the US and Britain is the spelling. Canadian spelling combines British and American rules, but the rules for Canadian spelling are not clearly defined. There are regional variations, and differences of opinion exist among editors. The official Canadian spelling is that used in the Hansard transcripts of the Parliament of Canada. The government style guide says that editors should consult the Gage Canadian Dictionary and go with the word used first. Many Canadian editors use the Canadian Oxford Dictionary, 2nd ed. (Toronto: Oxford University Press, 2004), and Editing Canadian English: The Essential Canadian Guide, 2nd ed. (Toronto: McClelland & Stewart, 2000).

In 1984 the Freelance Editors' Association of Canada (now called the Editors' Association of Canada) surveyed publishers, academics, PR people, editors and writers about their spelling preferences to get a better idea of what was the more common use. Some of the results are summarized below:

WORDS WITH -OUR/-OR: 75% of the sample preferred the use of -our such as colour, rather than color and favourite rather than favorite.

WORDS ENDING IN -RE/-ER: 89% of the sample preferred -re endings such as centre and theatre.

WORDS ENDING IN -SE/-CE: 80% of the sample preferred -ce over -se in nouns such as defence, practice and pretence, but let -se stand when such words were used as verbs, such as to practise the piano lesson.

DIPTHONG: 75% used the diphthong (ae or oe) in such words as aesthetic,archaeology and manoeuvre.

WORDS ENDING IN -IZE/-ISE: Canadian editors rejected the British -ise endings, such as organise, preferring -ize endings.

DOUBLING FINAL CONSONANTS: Up to 90% liked the double L in such words as enroll, fulfill, install, marvelled, marvellous, signalled, skillful, traveller and woollen.