Short answers, pulled from the story.
Larry Hama created the majority of the characters, writing the file cards and developing the overall concept from a shelved Marvel Comics pitch called Fury Force. Jim Shooter, then editor-in-chief of Marvel Comics, brokered the deal between Marvel and Hasbro. Archie Goodwin invented Cobra and the Cobra Commander.
The original toyline ran from 1982 to 1994, producing well over 500 figures and 250 vehicles and playsets. It returned as a Toys "R" Us exclusive in 1997 and 1998, and has continued in various forms to the present day.
A file card is a piece of cardboard packaging that accompanied most G.I. Joe and Cobra action figures, listing the character's code name, real name, serial number, birthplace, rank, military specialties, and a background paragraph. Larry Hama wrote the majority of these, especially across the first ten years, drawing on his own military experience.
The "Pimp Daddy Destro" (PDD) is considered one of the rarest G.I. Joe figures. Released in 1997 in the Cobra Command Team pack, it featured leopard-print accents on Destro's legs and was almost immediately replaced by a standard version. Only one verifiable mint-in-box copy and two loose versions are known to exist.
The Marvel Comics series ran from 1982 to 1994 for 155 issues, spawning several spin-off titles during its run. IDW Publishing revived the series in May 2010 with issue 155 and a half, continuing from issue 156 onward in July 2010 with original writer Larry Hama returning.
The file card for Cobra hypnotist Crystal Ball, released in the 1987 G.I. Joe toy line, was supposedly written by bestselling horror novelist Stephen King.