Huckleberry Finn, for whom the novel is named after, is the protagonist of the story. In the beginning Huck is portrayed as a troubled boy with a questionable past. Since Hucks father was an alcoholic and abusive, Huck lived with Miss Watson and the Widow Douglas. Society looked at Huck as if he were that kid, the kid who causes trouble, who is uneducated, and the kid to pity. However, Hucks intelligence and moral superiority to those who surrounded him is proven when he chooses to keep Miss Watsons slave, Jim, in hiding instead of turning him in. When Huck decided to do the morally correct option of keeping Jim safe, even though he could be sent to jail, shows what kind of character Huck is.
Jim, Miss Watsons slave, at first glance seems to be superstitious to the point of idiocy, but later on, the time that Huck and Jim spend on Jacksons Island reveals that Jims superstitions conceal a deep knowledge of the natural world and represent an alternate form of truth or intelligence. As Huck and Jim make their way down the river, Jim becomes a surrogate father to Huck, taking care of him without being intrusive or smothering. Jim cooks for the Huck and shelters him from some of the worst horrors that they encounter, including the sight of Paps corpse, and, the news of his fathers passing.
Jim is realistic about his situation and must find ways of accomplishing his goals without incurring the wrath of those who could turn him in. In this position, he is seldom able to act boldly or speak his mind. Nonetheless, despite these restrictions and constant fear, Jim consistently acts as a noble human being and a loyal friend. In fact, Jim could be described as the only real adult in the novel, and the only one who provides a positive, respectable example for Huck to follow.
Tom is the same age as Huck and his best friend. Whereas Hucks birth and upbringing have left him in poverty and on the margins of society, Tom has been raised in relative comfort. As a result, his beliefs are an unfortunate combination of what he has learned from the adults around him and the fanciful notions he has gleaned from reading romance and adventure novels. Tom believes in sticking strictly to rules, most of which have more to do with style than with morality or anyones welfare. Although Toms escapades are often funny, they also show just how disturbingly and unthinkingly cruel society can be.
Tom knows all along that Miss Watson has died and that Jim is now a free man, yet he is willing to allow Jim to remain a captive while he entertains himself with fantastic escape plans. Toms plotting tortures not only Jim, but Aunt Sally and Uncle Silas as well. In the end, although he is just a boy like Huck and is appealing in his zest for adventure and his unconscious wittiness, Tom embodies what a young, well-to-do white man is raised to become in the society of his time: self-centered with dominion over all.
In the novel, The Adventures of Huckleberry Finn, Twains plot driven story establishes the characters morality through their actions. Through Tom Sawyer, Huck Finn, and Jim, it is proven that it is character, not class that determines integrity. Through out the novel, each action Huck and Jim took made them stronger and smarter, while each action that Tom took made him crueler. Mark Twain wrote this novel not only to reflect on his childhood, but also to define the importance of a moral conscience.