'Someone' as a Pronoun
- Those indefinite pronouns made up of '-one' refer only to unspecified or unknown humans.
'Something' as a Pronoun
- Those indefinite pronouns made up of '-thing' refer only to unspecified or unknown things (non-humans).
'Someone' as a Noun
As a noun, 'someone' refers to an unnamed person we might or might not know.
Are you going to buy it for that special
'Something' as a Noun
'Something' as a noun can both refer to a person or thing of some importance. Remember that in this case it is used mostly in informal English.
She is really
You've never met Adam. He's