Meaning: There is absolutely NO difference in meaning between 'someone' and 'somebody'. Use: 'Someone' tends to be more common than 'somebody' in more formal and written contexts. The choice to use one word or the other is purely a matter of style and personal preference: for example, to improve the sound and rhythm of the sentence or to avoid repetition.

Nothing :)

There's a slight difference; Someone - tends to be more formal and abstract. Somebody - tends to be less formal and specific.

Nothing!

They're almost the same. They can be used interchangeably in almost all situations.