Second-person point of view is used when a main character is referred to with second-person pronouns such as "you." In non-fiction writing, second person is used primarily for technical writing and self-help books.
Second person is used in fictional writing, but it's considered confusing for the reader due to the usage of pronouns such as "you" and "yours." However, an author who wants to involve the reader more in the story can use it. Authors also wishing to place distance between a character and his or her actions can use second person. Nathaniel Hawthorne and William Faulkner both composed novels in second person.