"Who's" is a contraction of the words "who is" or "who has."
Example (who is): "Who's going to the party tonight?" Here, "who's" is short for "who is," indicating the question about who will attend the party.
Example (who has): "Who's been using my computer?" In this sentence, "who's" is short for "who has," indicating the question about who has been using the computer.
Whose:
"Whose" is a possessive pronoun that indicates ownership or possession.
Example: "Whose jacket is this?" Here, "whose" is used to ask about the ownership or possession of the jacket.
Example: "The person whose car was stolen reported it to the police." In this sentence, "whose" indicates the possession of the car by the person who reported it.
