You are aware that if many people observe the same event, they will each give a slightly different account. This is not unusual. They are not standing in exactly the same spot, so they do not see exactly the same things. They may or may not understand what they see or its significance. Each brings a different set of life experiences to the event, so they may interpret what they see differently. Some may confuse what they actually see with their interpretation of what they see!
The same is true of a writer.
Let's take a look at the most used viewpoints. To do this, first realize that the writer may write with one of these three degrees of insight into his characters:
Next, let us examine the person the writer chooses:
Crossing these two concepts in a 3 x 2 matrix, we arrive at the following six possible combinations:
Unless your character is supernatural and can read other people's minds and motivations, first person omniscient will seem extremely unnatural to your reader. This is also true of first person limited omniscient. First person objective makes sense, since real people are limited to what they can see and hear of others. The writer using the first person objective point of view can still reveal the motivations of other characters through their actions, but he cannot read their minds!
All three of the third person viewpoints are valid. The author is not one of the characters. He is the author and can choose to know the characters' thoughts and motivations in part or in whole for all, any, or none of his characters. If the narrator of the story is a minor character, he will have a mixture of first and third person accounts. Those things that involved him, he will report in first person. Those things that involved the main character and others will be revealed in third person.
The final tally: only four of the six possibilities actually work without giving a strange, unreal feel to the narrative. Limit your choices of viewpoints to one of these four:
That depends on your story. Will the death of your friend be more compelling if you are writing in first person about a loss you have personally experienced, or in third person about someone else's loss? Is the super-hero you--in first person--or is he someone from Krypton--in third person? Are you the famous sleuth telling of his own, first-person adventures, or are you Dr. Watson, telling in a mixture of first person and third person, those events you witnessed or in which you participated with the Great Sherlock Holmes?