It's used to address multiple people (you all, you guys, etc.).
Here are some examples:
* "¿Tenéis hambre?" - "Are you hungry?" (to a group of people)
* "Tenéis que ir al supermercado." - "You need to go to the supermarket." (to a group of people)
* "Tenéis una hermosa casa." - "You have a beautiful house." (to a group of people)