It was designed in 1958 by Gerald Holtom for the Campaign for Nuclear Disarmament, although it was later adopted into a general peace symbol. The symbol represents, in a rather convoluted manner, the letters "ND," for "Nuclear Disarmament." The semaphore flag signal for "N" is basically flags at the positions of 4:30 and 7:30 on a clock, (forming what look like the "wings" of the "airplane" within the circle), while the semaphore signal for "D" is flags at 6:00 and 12:00 (forming the "fuselage" of the "airplane."), all within a circle.