The narrator is the person or intelligence telling the story.
It could be first person, like in The Vampire Lestat, in which Lestat tells his side of the story (in response to the first book, which centered around Louis). Lestat begins his tale thus: "I am the Vampire Lestat. I'm immortal. More or less. The light of the sun, the sustained heat of an intense fire -- these things might destroy me. But then again, they might not."
It could be second person, which is rare, but beautifully rendered in this example from Lorrie Moore's "How to become a Writer": "First, try to be something, anything, else. A movie star/astronaut. A movie star/missionary. A movie star/kindergarten teacher. President of the World. Fail miserably. It is best if you fail at an early age -- say, fourteen. Early, critical disillusionment is necessary so that at fifteen you can write long haiku sentences about thwarted desire. It is a pond, a cherry blossom, a wind brushing against sparrow wing leaving for mountain. Count the syllables. Show it to your mom."*
Or it could be third person, which allows for a wide variance in perspectives:
1. Objectively report what is happening;
2. Go into the mind of any character;
3. Interpret for us that character's appearance, speech, actions, and thoughts, even if the character cannot do so;
4. Move freely in time or space to give us a panoramic, telescopic, microsopic, or historical view; tell us what has happened elsewhere or in the past or what will happen in the future; and
5. Provide general reflections, judgments, and truths.
In all these aspects, we [the reader] will accept what the omniscient author tells us.* *
Here is how Tad William's The Dragonbone Chair begins: "On this day of days there was an unfamiliar stirring deep inside the dozing heart of the Hayholt, in the castle's bewildering warren of quiet passages and overgrown, ivy-choked courtyards, in the monk's holes and damp, shadowed chambers. Courtiers and servants alike goggled and whispered. Scullions exchanged significant glances across the washing tubs in the steamy kitchen. Hushed conversations seemed to be taking place in every hallway and dooryard and dooryard of the great keep."
* Janet Burroway/Writing Fiction, p.206
** Janet Burroway/Writing Fiction, p.201
Do you have a preference for narrators?