Its basically a patched version of fontconfig with "The purpose of these patches is to freely provide the nicest font rendering of any operating system."
With few commands and X restart, the font rendering is so beautiful, that my eyes still enter "Holy shit!" mode when reading pages on docs.python.org. The font appearance is actually much better then Windows 7 does - Windows fonts are very sharp edge. They make my eyes tired at the end of the day. Infinality fonts are much smoother and at the same time are not blurry.
Try that on your linux box. You would not regret!
sudo add-apt-repository ppa:no1wantdthisname/ppa sudo apt-get update sudo apt-get install fontconfig-infinalityRestart your X and you are set.