Why is Quebec French different to the French spoken today in France?

In the Canadian province of Quebec, people have their own dialect of the French language. This dialect is built largely on old-fashioned and traditional French phrases, whilst also showing influence of American/US English. For example, someone who speaks Quebec French will be more likely to refer to someone using the pronoun 'tu', regardless of their age, gender or authority (where the pronoun 'vous' is often used as a mark of respect in the modern French language). As well as some special tailored French-Canadian words, some speakers of Quebec French use different pronunciations for word like 'fête' (changes to 'fight') and 'pas' (changes to 'paw').