old ataris did for sure you could play 2600 games on the 5200 in 2600 mode. Also the mega drive could play Master system games with a simple form convertor (no additional hardware) and the Gameboy range always maintained one lvl of backwards compatibility all the way to the 3DS.
PS2 was the first system I know of that had a media remote control for dvd's and cd playing ability.
PS2 would have been the first system out capable of doing HD output in a comercial game (GT4 had 720p or 1080i in a mode)
Was the Psone the first system with removable memory cards? ... I know that the saturn was a cd based system but it's memory was 100% not removable from the system... not sure about this one.
eerrr.... Ps3 was the first system where people tried to claim it had no games for years after there was infact hundreds of games?
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