In the history of video games, the fourth generation of game consoles, more commonly referred to as the 16-bit era, began on October 30, 1987, with the Japanese release of NEC Home Electronics' PC Engine (known as the TurboGrafx-16 in North America). Although NEC released the first console of this era, sales were mostly dominated by the rivalry between Sega and Nintendo across most markets: the Sega Mega Drive (Sega Genesis in North America) and the Super Nintendo Entertainment System (SNES; Super Famicom in Japan). Cartridge-based handheld consoles became prominent during this time, such as the Nintendo Game Boy (1989), Atari Lynx (1989), Sega Game Gear (1990) and NEC TurboExpress (1990).