First person – simply, this is when the ‘I’ (or ‘We’) tells the story. This is the way you’d naturally tells a story about something that happened to you and you were probably asked to write this way as a child when your teacher asked you to write a daily ‘news’ exercise or an essay on ‘what I did during the holidays’.
“The doctor was doing that thing where they talk to you but don’t look at you, reading my notes on the screen, hitting the return key with increasing ferocity as he scrolled down.
'What can I do for you this time, Miss Oliphant?’
‘It’s back pain, Doctor,’ I told him. ‘I’ve been in agony.’ He still didn’t look at me.
‘How long have you been experiencing this?’ he said.
‘A couple of weeks,’ I told him. He nodded. ‘I think I know what’s causing it,’ I said, ‘but I wanted to get your opinion.’ He stopped reading, finally looked across at me.
‘What is it that you think is causing your back pain, Miss Oliphant?’
‘I think it’s my breasts, Doctor,’ I told him.
‘Yes,’ I said. ‘You see, I’ve weighed them, and they’re almost half a stone – combined weight, that is, not each!’ I laughed. He stared at me, not laughing. ‘That’s a lot of weight to carry around, isn’t it?’ I asked him. ‘I mean, if I were to strap half a stone of additional flesh to your chest and force you to walk around all day like that, your back would hurt too, wouldn’t it?’
He stared at me, then cleared his throat.”
This story is being told in the first person POV from Eleanor's perspective.
The doctor is looking at her notes and'hitting the return key with increasing ferocity as he scrolled down' and then when he turns to her and asks what he can do for her 'this time' that gives us readers a clue that perhaps she is a regular visitor and demanding.
Eleanor laughs, he stares at her and doesn't laugh. Then she explains what she believes is causing the back ache and the doctor stares at Eleanor and 'then cleared his throat' .
Notice that we have no access to what the doctor is thinking or feeling and the author has to let us infer his thoughts and mood from Eleanor's observations of his behaviour. We can only see the world from Eleanor's POV and this creates an intimacy with Eleanor: we can see the world as she sees it. In this novel Eleanor Oliphant is the protagonist (main character) of the story but that isn't necessarily the case.
Sherlock Holmes stories are told by Watson as the first person narrator while Holmes is the protagonist.
The Poisonwood Bible by Barbara Kingsolver uses five first person narrators (a mother and her four daughters) to tell their story. The father, Nathan Price, is also a central character but he has no voice in the narration.