Point of View - What is it?
It's the perspective from which a story is told. When writing a novel, an author must decide who is telling the story. Based on that decision, the author will write in either first, second or third person.
FIRST PERSON - Using "I" throughout the manuscript.
SECOND PERSON - Where "You" is the descriptive.
THIRD PERSON - When He or She is used to describe the main character.
Once you've decided which person you'd prefer to use, you'll need to clearly define what the person sees, feels and experiences. When that character takes the stage, everything should be from that character's point of view. He or she cannot see or hear or know about anything outside his or her realm.
Example: A character can't see what's happening in another room with some other character without actually being in that room.
The author should make it obvious to the reader whose point of view is being used in each instance or confusion and/or irritation will result. Switching back and forth is called Head Hopping and a sign of a novice writer.
Skillful writers can travel from one to another character's viewpoint in the same paragraph, but the general rule is to keep in one point of view for each scene or even an entire chapter. When a switch is made, it should blend in with transitions and not be abrupt.
The exception for employing various points of view is the choice of using omniscent point of view, where the author is almost like another character looking down at the main characters and describing everything that happens to each person. Very skilled or very popular writers can pull this off, but it's not the general path to follow.
Following the tried and true rules will show publishers and readers that you understand the basic concepts of writing, so remember to follow them when considering point of view in your manuscript.