The keys on the keyboard that do things other than type. Called so because they're often in a darker grey than the letter-number ones.

On the AmstradCPC the "GreyKeys" were, on the 464, bright green, bright blue for the "enter" keys, and bright red for "escape" with the main keyboard black, giving it a rather Duplo look. --KatieLucas

The function keys on my old AtariSt were once the same color as the case, but now after some years of decay and sun burn, they became GreyKeys of another (somewhat darker) color than the case. -- GunnarZarncke
''Yuch!'' -- AalbertTorsius
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CategoryHardware