Originally published by National comics, as a stroy about a man, alan scott, granted powers by, literally, a Green Lantern. During the silver age of comics, National (now DC) reintroduced the character, this time an inter gallactic law inforcer named Hal Jordan. Since that time the role of green lantern has been filled by John Stewart, Guy Gardner, and most recently, Kyle Rayner.
The original, Alan Scott, resides on DC's Earth2, and now goes by Sentinel. Hal Jordan died after becoming obssed with power (nd becoming the being Paralax) but was resurected as
The Spectre. He has since given up that identity. Kyle Rayner acts as Earths green lantern, and Guy Gardner and John Stewart continue to act as superheros within
the Green Lantern Corps.