Listed here are some key terms–and their definitions–pertaining to writing:
diatribe – a forceful or bitter attack against someone or something.
epistolary – relating to or denoting the writing of letters or literary works in the form of letters.
expository writing – explains, describes, gives information, or informs; the text is organized around one topic and developed according to a pattern or combination of patterns.
irony – the expression of one’s meaning by using language that normally signifies the opposite, typically for humorous or emphatic effect.
novella – a short novel or long short story.
polemic – a strong written or verbal attack on someone or something.
satire – the use of humor, irony, exaggeration, or ridicule to expose and criticize people’s stupidity or vices, particularly in the context of contemporary politics and other topical issues.
vignette – a brief evocative description, account or episode.
All definitions from Google.
A more extensive list of literary terms can be found on the Literary Terms webpage of the Purdue OWL.