A first-person viewpoint features the main character narrating the story. The pronouns "I," "me" and "my" appear frequently. The first-person point of view helps the reader understand the character, his thoughts, feelings and secrets. It creates an intimate bond between the reader and the narrator, and makes the reader empathize with the narrator. However, the first-person point of view removes all objectivity, as the narrator can provide only one perspective of the events and incidents depicted in the book.
The second-person viewpoint uses the pronoun "you." This point of view is rather limited, so it is not popularly used in fiction writing, aside from "Choose Your Own Adventure" books. Non-fiction writing often uses this narrative, particularly in self-help books, advertisements, brochures and cookbooks, which gives instructions. For example, “You take a cup of flour and add some butter to it."
Omniscient point of view uses the pronouns "he," "she," "it" and "they" to tell the story. The narrator is not part of the action, and this gives him objectivity. He tells us about the different characters in the story without bias toward any of them. The narrator looks into the minds of all the characters, and sometimes "hops" from one head to another in a single scene. This helps the reader understand what all the characters are doing and thinking.
This narrative type also uses the pronouns "he," "she," "it" and "they," but the reader stays firmly with one character at a time. The character can only report what has happened, and cannot look into the minds and motives of the other characters, beyond basic speculation. Character "switches" may take place during scene or chapter breaks. This is the most common type of narrative.