What Is Clearance?

If you hear some one say roger on an aircraft, they're saying, i have received all of your transmission, so i've listened to you. Another expression used in the scene, which we've put a link to in the show notes, is clearance. Now, that's not about making something clear or clean. It's not like taking things off a table. No, whenever you talk about clearance in flight or travel in aircraft, you're talking about the authorization by the air traffic control. And if a pilot is asked for their vector, v, e cto r, they are being asked for their heading, for their direction. Which way are they flying, which way are