A lamp of an autonomous vehicle may include at least one light emitting unit. The lamp may further include at least one processor configured to: in a first state in which the autonomous vehicle is operating in a manual driving state, control the at least one light emitting unit to emit a light into a space outside the autonomous vehicle; and in a second state in which the autonomous vehicle is transitioned from the manual driving state to an autonomous driving state, control the at least one light emitting unit to not emit a light into the space outside the autonomous vehicle.