Alliteration - The same initial sound to words.
Assonance - Repetition of the vowel sound.
Onomatopoeia - Words that sound like the word itself (Boom, Whistling)
Personification - Giving something human qualities. (The stream was running)
Simile - Describing something as something else, usually with the word like or as.
Metaphor - To replace one image with another.