Writers have several options when choosing which point of view to use when writing fiction. Since I have no experience whatsoever with writing in the first person, this post shall be limited to the one suggested by most instructors (limited third person) and how it differs from one I have noticed in some other new writers' works (omniscient)...including my own.
A limited third person point of view allows the reader to know the thoughts of the main characters in a story.
The omniscient point of view gives the reader everyone's thoughts, sometimes including the writer's.
Everything I have read about point of view recommends the use of limited third person and strongly discourages the use of omniscient POV.
Most people who read fiction want to identify with a character in the story. They invest a part of themselves into that character, and for better or worse, say to themselves either, "That could be me" or "I wish that were me".
People can't emotionally invest in every character in the book. And if they are constantly made privy to the thoughts and motives behind every character, rather than better understanding the story (as young authors believe will be the case by sharing every internal detail), the opposite happens. The reader feels disconnected from all the characters.
Experts say it is better storytelling to choose to reveal on the main characters' internal musings. I have struggled with this personally. I wanted my readers to understand what all the characters in the room were thinking, feeling that it helped to better explain their actions. However, it was pointed out to me that since we as readers connect with only one character at a time, it is better to choose one character and relate the whole scene from his point of view. Now, as writers we can still show what other characters are thinking through the eyes of the main character.
Let's look at two examples:
Mike wanted desperately not to be the last person chosen this time. He stood as tall as he could, puffed his chest out as much as he dared and held his head high. Joe and Tim, the team captains stood at the front of the group. Joe looked at all the other boys, and picked the ones he thought had the best athletic ability. He hated to lose. Tim was more thoughtful. He didn't like to see anyone left out, and he had noticed that Mike was often chosen last.
This is an example of omniscient point of view. We know what Mike and Joe and Tim all think. And its difficult to connect with anyone, because we know what everyone is thinking! Let's look at the same scene strictly from Mike's point of view:
Mike wanted desperately not to be the last person chosen this time. He stood as tall as he could, puffed his chest out as much as he dared and held his head high. Joe and Tim, the team captains stood at the front of the group. When it was Joe's turn to choose, Mike made a concerted effort to make eye contact. He watched Joe scan the faces of the other boys in line. For a split second their gazes locked, and Mike held his breath. Then just as quickly Joe's gaze moved down the line. Mike let his breath out slowly, like a deflated balloon, as Joe remained true to form and chose the best pitcher.
Next it was Tim's turn. Mike's heart hammered in his chest and his hands felt sweaty as he waited for Tim to make his choice. He closed his eyes for a moment, willing Tim to see him, to really see him. When he opened his eyes, Tim was looking right at him. Unlike Joe, Tim's gaze didn't skitter away immediately. He seemed to ponder his choice carefully. Please, thought Mike. Please pick me.
Who do you, the reader, identify with? Mike, of course. We see the whole scene unfold through his eyes. We feel his emotions, and we long for him to be chosen as well. Do we still get a sense of Joe's and Tim's character? Absolutely. Can we imagine what those two boys are thinking by their actions? Yes. And yet we weren't told their thoughts...we were shown their thoughts through Mike's interpretation of their actions.
For more on this discussion, check out the following link from award winning author, Robert J Sawyer: