* It's empty: This is the correct spelling and means something is lacking content or substance. For example, "The refrigerator is empty."
* It's empty. This is the same meaning as above, but with a more emphatic tone, often used to express disappointment or surprise.
* Its empty: This phrase could refer to something belonging to something else that is empty. For example, "The dog's bowl is empty, but its water bowl is full."
To understand the meaning of "its empty" in a specific context, you need to look at the surrounding words and phrases.