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Standard English is a general term for a form of written and spoken English that is considered the model for educated people by native English speakers. There are no set rules or vocabulary for "Standard English" because, unlike languages such as French or Dutch, English does not have a governing body (see Académie française, Dutch Language Union) to establish usage. As a result, the concept of "standard English" tends to be fluid. Various regional and national "standards" exist.
The issue is particularly complicated because English has become the most widely used language in the world, and therefore it is the language most subject to alteration by non-native speakers.
The two most common recognised varieties of English are British English (which very broadly includes the British-based dialects of English spoken in Australia, New Zealand, and South Africa) and American English. However notwithstanding the various historical migrations of English-speaking populations, colonisation and the bastardising effects of local native languages resulting in such language offshoots as creole or pidgin, English has risen to being a lingua franca, primarily due to its pre-eminence as an international trade language, and its widespread use outside purely English-speaking countries has given rise to many local varieties of English. Standard English is a language, not an accent; that is, it refers to a set of words, grammar, and linguistic sounds, not to a particular pronunciation.