On the first page of Fahrenheit 451, the fireman's hose is called a "python." The reader knows it is not literally "a snake," but the use of the word python connotes the idea that the fire-spitting hose is alive and since serpents are often linked to evil symbolism (the serpent in the Garden of Eden being the most prolific evil serpent symbol in Western Christianity), that symbol might also be inferred.
There are quite a few similes in this book. On my page 9, Montag imagines Clarisse's face "like the dial of a small clock," which tells you the time in the dark and also foretells the change to come with tomorrow's sunrise. For Montag, his interactions with Clarisse were an awakening.
On the first page of Part III, "Burning Bright," Beatty (who, like Faber, does have a relatively considerable knowledge of literature) tells Montag, "Old Montag wanted to fly near the sun and now that he's burnt his wings, he wonders why" (100). Beatty is speaking figuratively. He is referring to the mythical Icarus who was warned not to fly too close to the sun. Icarus is curious and does just that. His wings melt and he crashes into the sea. Themes of this myth include ambition, curiosity, desire for knowledge, and questioning authority. It is often cited as a cautionary tale, but it is also cited as a form of rebellion. Beatty knows this literary reference and uses it as a cautionary tale. However, Montag (flew too close to the sun = read books and questioned society) rebelled because he wanted to be an active, free thinker.
This last example is a use of figurative language which includes a literary reference (to the myth) and this is also a metaphor or an allegory.
There is also quite a bit of zoomorphism (speaking of things in animalistic terms). At one point, Faber tells Montag he talks about the meaning of things; not just things. Speaking of the hose, the helmets (beetles), and most importantly the books as if they were alive connotes the idea that these are not just things: they also have life or meaning. When Beatty orders Montag to burn his own house (also in Part III), the narration is "The books leapt and danced like roasted birds, their wings ablaze with red and yellow feathers" (103).
This is one of the main themes of the book. When meaning is enriched (figurative language is one of the ways this is done), life is enriched. To someone like Clarisse (and Montag, after his "awakening"), a bird is not just a bird; it symbolizes flight, song, freedom, etc. For Montag, books become "alive with meaning" and later he and the book people he meets become books: a strong connection between books/meaning and life. The characters who do not think this way are more robotic. They fear literature and figurative language because it complicates their simplistic, thoughtless life.