Imagery: collective images of descriptive language. Example: "When shall we three meet again? In thunder, lightning, or in rain?"-Macbeth. This creates an ominous atmosphere in the onset of the play.
Juxtaposition: usually unassimilated words, phrases, ideas, placed next to each other which give us a sense of irony. Example: "Not that I loved Caesar less, but that I loved Rome more."-Julius Caesar.
Metaphor: one object is directly compared to another object. Example: "Now is the winter of our discontent, Made glorious summer by this son of York."-Richard III.
Onomatopoeia: sound words. Example: "There be more wasps that buzz about his nose."-Henry VIII.
Pathetic fallacy: personification of nature. Example: the earth is sensitive to the plight of man.
Personification: inanimate objects having life-like qualities. Example: "Earth felt the wound; and Nature from her seat, sighing, through all her works, gave signs of woe"-Paradise Lost.
Protagonist: the central character. Example: Shakespeare's Othello, Othello is the protagonist.
Rising action: building up of events to the climax or crisis. Example: Shakespeare’s Hamlet, a ghost resembling his father appears to Hamlet and imparts on him to take revenge on his murder.
Simile: comparison using the words “like" or “as". Example: "Doubtful it stood; As two spent swimmers, that do cling together And choke their art."-Macbeth.
Situational irony: discrepancy between expectation and realization. Example: Shakespear's Macbeth, Macbeth kills Duncan to gain the throne, and thinks only of the power and wealth he will enjoy as the new King of Scotland.
Symbolism: concrete idea that stands for some general idea. Example: lily for purity, sunshine for hope, heart for love. You'll find a great discussion about symbolism here.
Theme: central idea. Example: Shakespeare's Macbeth, the main theme is corruption brought by unchecked ambition. The idea of theme in a novel is further discussed here.
Tragic flaw: a flaw which eventually leads a character to downfall. Example: Shakespear's Hamlet, Hamlet's tragic flaw is his inability to act, to revenge his father's murder.
Verbal irony: the opposite of what is said is meant. Example: Jane Austin's Pride and Prejudice, Mr. Bennett refers to Wickham as perhaps his "favorite" son-in-law.