A font rendering technology in Windows XP that smooths the edges of diagonal lines and makes text more readable. To turn ClearType on, select Effects in the Appearance tab in the Display control panel, and switch from Standard to ClearType. For more information, visit www.microsoft.com/typography/WhatIsClearType.mspx.
Standard Vs. ClearType
Note the smoother appearance in the ClearType example on the bottom.