Source of version: 2 (current)
ClearType is a way to use the individual colors of pixels to improve the way TrueType fonts look. It depends on the way that the LCD is cut or the screen is rotated. In order for ClearType to work the colored pixels have to be horizontal.
See [http://www.pocketpcfaq.com/comdex98.htm|Comdex 98 - ClearType]
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