For instance, your main character, let's say his name is Joe, is telling the story, so the pronoun used throughout will be "I". This is "First Person Point of View" and only those things that Joe sees, hears, or could possibly know, can be written about in the story.
First person and Third person are the points of view most commonly used. With third person, we have a couple of sub-sets. Someone outside the story would be omnicient, meaning 'like God' and able to see and hear and know everything about everyone in the story. Limited third person means a "narrator" telling the story as if they were inside a character.
Moving from one character to another should be done very carefully. If not, the reader will be confused and have to keep flipping back through the pages to work out where they are viewing the story from.
A simple way to understand point of view is to think of it as a camera device:
- implanted into one character's head, unable to move from there, with the story told by that one person who addresses himself or herself as "I". This is First Person Point of View.
- implanted into one character's head, and able to move from there into the head of another, but only after all pictures and sound have been removed. Thus, the 'camera' does not take any information from one character to another. The character that has the camera implanted is the one who will be named, as "Joe said" or "Joe did or thought"; then "Mary did or thought" and so on. This is one sub-set of Third Person Point of View.
- implanted into only one characters head, and stays there for the whole story. With this point of view, the character will be named as, "Joe said" or "Joe did this or that" or Joe thought". This is a limited Third Person Point of View, meaning that it is limited to only one character.
- able to move freely into the heads of all characters, knowing everything, but not letting the characters know everything unless the character has seen, heard or experienced it for themselves in the story. The omniscient narrator sees everything from within and without, is able to roam above and through the characters. This is Omniscient Point of View - like God, able to see, know and understand everything about everyone.
I hope this explains it a little better for the person who posted a comment. The only other thing I can suggest is that you read a selection of books and try to see for yourself how the writer reveals the story - whether it's from the view of one character only or from many, or from within or without the character/s.