who's

 
Pronunciation: /huːz/

contraction

  • who is: who’s that?
  • who has: who’s done the reading?

A common written mistake is to confuse who’s with whose. The form who’s represents a contraction of ‘who is’ or ‘who has’, while whose is a possessive pronoun or determiner used in questions, as in whose is this? or whose turn is it?.