Generation 1 is the fan-designated name for the original series of G.I. Joe: A Real American Hero toys launched in 1982, as well as the follow up 1997-2002 series known as The Real American Hero Collection, which shared the same moulds and construction as the original series.
The first "generation" of the toy line, simply titled "G.I. Joe: A Real American Hero," was a line of military themed action figures. This classic series of action figures relaunched the G.I. Joe brand and became the basis for every incarnation of the G.I. Joe vs. Cobra theme, and nearly every version of the brand since.