Salinger uses simile in the first chapter when he has Holden write,
Anyway, it was December and all, and it was cold as a witch's teat.
A simile is a comparison using the words "like" or "as." Here ,Holden compares the cold weather to a witch's teat, or nipple. This also characterizes Holden: it is typical of him, as he is a teenager who has girls on his mind, to compare cold weather to an icy-cold female body part. Another example is when he jumps on Stradlater:
I landed on him like a goddam panther.
Holden uses imagery as he describes visiting his elderly teacher, Mr. Spencer, in his home. Imagery is description using the five senses of sight, sound, touch, taste, and smell:
He was reading the Atlantic Monthly, and there were pills and medicine all over the place, and everything smelled like Vicks Nose Drops.
The above quote contains not only visual images, but also a scent image that helps place the reader in the scene.
Holden loves to use hyperbole, or exaggeration. He says of Stradlater:
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