THE PORTABLES
In the late eighties Nintendo started to develop something entirely new , it was called the Game Boy it would change gaming completely The system itself was very small but the display was not quite spectacular , it was a black and white ,.. I mean a yellow black passive matrix (most called a dot matrix screen) like tamagotchis and most personal organisers have , with four yellows the first game which came with it was Tetris and afterwards followed the mario's and others , other game makers smelled something new and started develloping their own handheld systems .
First came Atari with their Lynx ... This one was more spectacular it was a portable 16 bit system equipped with a 16 color passive matrix screen , this was a much better one , unfortunately this system was very fast with batteries and was therefore supplied with a adaptor and a 12-volt adeptor , but with all other Atari products , they died fast , this was 1990 now the only place where you can find a Lynx is in a discount bin for 24 dollar and 5 dollar a game (That means it is really dead) , afterwards came the Sega Game Gear and the Turbo Express , Sega claimed that all games for the Mark III or the master system fitted in the Game Gear , due to space reasons this could not be realised , but with a convertor this could also be done , this was a eight bit game console with a 32 color passive matrix screen (it has some problems with the contrast , you can't get it right) and with all passive matrix screens you can't use it in sunlight , but it had a very large game support and therefore it's with the Gameboy the most succesfull handheld .
Also that year came the Turbo Express a very spectacular system equipped with a razor sharp active matrix screen (TFT) and super high sound quality , and you could play all the Turbografix games (or PC-Engine games-with a converter) in sunlight or in the dark
Later in 1995 came the Virtual Boy from Nintendo which was no serious attempt to make a portable 32 bit system but more a novelty (it was not very portable) it had a one color dot matrix screen the only color was red and a 11 MHz Risc processor , It looked like a pair of night gogles with a joystick on a string on it , it had not much games and most were just average  , Later in 1997 came the Sega Nomad the second handheld with a active matrix screen almost as good as the Turbo Express and a 7,6 MHz motorola 68000 CPU and Zylog 80 sound processor , and like the Turbo Express this is a miniature version of the Genesis/Mega Drive so you can play all your Genesis games . In this year Tiger also made a handheld , the Game.com  (a gameboy wannabe) with a touchscreen a phone dialer , Internet Modem , and a small organiser inside and the game wheel of fortune , The screen looked the same as the gameboy but it has a touchscreen with a resolution of 200 x 160 and four gray shades and has a eight bit processor . And Nintendo improved the Game Boy , they made it smaller , Now Nintendo is working on a color version of the Game Boy it boast a color screen of 51 colors at a time from a pallette of 32000 colors also 8 bit all old gameboy games are compatible with this one with a selectable 8 color pallette , This one will be released this year in June and next year in Europe (Nintendo's words) . Don't take this too serious you know how Nintendo is (remember the N64) .