Aircraft tails consist of two part, which is two small horizontal part and one vertical part.The two small horizontal part which have small tab on it which is called the "Elevator", those elevator helps the aircraft to pitch up and pitch down during take off/in flight/landing. Elevator also helps to keep the aircraft level when the autopilot is engaged, the autopilot will automatically pitch up and down to keep the aircraft level during cruising. As for the vertical part, which also has tab on it which is called the "Rudders", these rudders helps the aircraft to yaw left and right during take off/landing. By using rudders, it helps to keep the aircraft aligned to center of the runway during take off and landing.