Year:1990
The Gameboy is one of the most sold consoles in the world and was the best sold portable Console for a long time. First, the Gameboy was sold with the Game Tetris, which became the most sold Game of the History
Year:1998
The Game Boy Color was the first portable Console with a colored Display, and it could choose between 32.768 Colors. The older ones had a Display with four types of Grey, witch replace the Game Boy Color in Black, Blue, Red and Yellow (and White as the Background)
Year:2001
The Game Boy Advance was the first model of the Game-Boy-Line, which isn't based on the technic of the normal Gameboy. This Console also got a colordisplay like the Game Boy Color, and it also called Super Nintendo Entertainment System in Pocket size.
Year:2003
The Game Boy Advance SP was a comfort-revision of the GBA. The Game Boy Advance SP is hinged and got some backlighting, so you can play in the dark. First there was a Frontlight, later there were devices, which got a backlight.
Year:2005
The Gameboy Micro is the smallest model of the Gameboy series. The Hardware is identical to the Game Boy Advance and the Game Boy Advance SP. But the Game Boy Micro is only with Game-Boy-Advance-Games compatible.