If you order from Starbucks regularly, you know that there are three cup size options: tall, grande, and venti. But what you might not realize is that there are two other sizes as well. First is an 8-ounce "short" cup, which is what the kid's hot chocolate is served in. You can ask for it for anything, though. Then there's the Trenta, which holds 31 ounces and is only for iced drinks.