5 things to know about GI Joe as he turns 50

Five things to know about G.I. Joe, the action figure that's turning 50 this year:

YOU SAY IT'S YOUR BIRTHDAY: G.I. Joe was introduced in either February or March 1964, depending on whom you ask. Collectors and the manufacturer, Hasbro Inc., say it was February at the American International Toy Fair in New York. But fair organizers say it was held in March that year.

TOY AS TRIBUTE: Don Levine, Hasbro's head of research and development, came up with the idea while returning home from combat as an Army infantry sergeant in the Korean War. “We protected each other and loved each other,” Levine said this week. “Something had to be done to honor these people.”

40 YEARS TO FAME: G.I. Joe hit shelves in time for Christmas 1964, going on sale for $4 apiece in boxes identifying him as “America's Moveable Fighting Man.” It was inducted into the National Toy Hall of Fame in 2004.

A DEATH AND REBIRTH: Sales sank in reaction to the Vietnam War, leading to a line “Adventure Team” G.I. Joes that played down the military connection. Production was halted in the 1970s. In the early 1980s, G.I. Joe was reintroduced as 3¾-inch figures.

PASSIONATE FAN BASE: It has an official G.I. Joe Collector's Club, which holds an annual “GIJoeCon” convention. This year it's in April in Dallas.