Moby Dick is a famous novel written by Herman Melville.
When the narrator, Ishmael, goes out with a newfound friend on a whaling expedition, he does not know what will fall upon him. Throughout this tale, the crew on the Pequod (the ship) is searching for the Great White Whale, Moby Dick. Their captain, Captain Ahab, had his leg taken from him by this whale, and now he is out for revenge. This book is filled with chaos as the crew tries so hard to find that whale and kill it.
The meaning of Moby Dick is probably the most disputed part of the novel. Moby Dick is said, by some, including the deranged Captain Ahab, to be symbolic of all that is evil, passion and even life itself. We, the audience, are positioned to perceive Moby Dick in many different ways, but according to how Ahab acts towards the whale, with an inconceivable hatred and irrevocable lust for vengeance. In this light, you can understand why to some people Moby Dick may be a symbol of all that is evil, romance, certain government policies (not kidding), and even life itself.
Moby Dick also symbolizes the unknowable, what individuals chase but can never catch. He spends most of the time submerged beneath the waves, out of sight, only view able in glimpses and fragments. In some sense, the pursuit of Moby Dick symbolizes the pursuit of a whole and lasting truth, a complete representation and understanding of nature and man's place in existence, which, of course, we can never have but for which Ahab dies at the conclusion of his ultimately futile venture.
The ugly ship that the whaling crew sails on is a symbol of doom. It is painted black and covered in the teeth and bones of whales. It is painted a gloomy black and covered in whale teeth and bones, literally bristling with the mementos of violent death. It is, in fact, marked for death. Adorned like a primitive coffin, the Pequod becomes one. The name 'The Pequod' itself is derived from an early Native American people that were destroyed by white settlers. Thus, 'The Pequod' represents destruction.
Queequeg's coffin alternately symbolizes life and death. Queequeg has it built when he is seriously ill, but when he recovers, it becomes a chest to hold his belongings and an emblem of his will to live. He perpetuates the knowledge tattooed on his body by carving it onto the coffin's lid. The coffin further comes to symbolize life, in a morbid way, when it replaces the Pequod's life buoy. When the Pequod sinks, the coffin becomes Ishmael's buoy, saving not only his life but the life of the narrative that he will pass on. (Generally symbolizes bringing forth life, from death.)