Who uses the designation DEAF? drphil and people who think yelling at someone who can't hear will help. Nope. You've got Deaf here, you have deaf here, you have hearing here, you even have one or two deaf that claim to hear like a hearing person with their device. But DEAF? Nope. Don't exist except in your mind.
Let's not mislead this young man in his attempt to understand and write a dissertation on the topic, drphil. He doesn't need you adding confusion into his task.