It debuted the year the Chevy Impala was introduced, the hula hoop was the national craze and the United States launched its first satellite.

Fifty years ago today, an odd-looking symbol went public in London's Trafalgar Square at the start of Britain's first major demonstration against nuclear weapons.

It became known as the peace sign and was designed by Gerald Holtom, a London textile designer, for a demonstration by a disarmament group called the Direct Action Campaign. The group planned a 52-mile march from London to the town of Aldermaston, where an atomic weapons research center was based.

In creating the sign, Mr. Holtom combined the semaphore -- flag signaling alphabet -- signals for the letters N, for nuclear, and D, for disarmament. He felt the group's message would have more impact if it carried a strong symbol.

The symbol quickly became a popular icon, and has endured through the Vietnam War, the civil rights movement, the environmental movement, women's and gay rights movements and the two Iraqi wars.

It's the focus of a new book, "Peace: The Biography of a Symbol" (National Geographic Books, $25), by Ken Kolsbun, with Michael Sweeney, that was released April 1.

Mr. Holtom, a conscientious objector during World War II who died in 1985, once described his design with these words:

"I drew myself: the representative of an individual in despair, with hands, palm outstretched outward and downward, in the manner of Goya's peasant before the firing squad."

-- Virginia Linn