The document discusses different levels and contexts of language usage including register, style, formal vs informal language, and vulgar or taboo language. It notes that register and style refer to vocabulary, idioms, syntax and grammatical structures used. Spoken language tends to be more informal while written is more formal, impersonal and precise. Levels of language include formal, informal and vulgar. Formal English is used for writing and serious topics while informal English uses simpler grammar and vocabulary from Germanic roots. Vulgar language touches on taboos and is not generally used in writing.