When you install Fedora 15, you are provided with the default font look that is too thin, and quite difficult to read after a long time. It is quite a strain on the eyes. To improve the quality of fonts, you should do:
# ln -s /etc/fonts/conf.avail/10-autohint.conf /etc/fonts/conf.d/ <enter>
You can optionally also install the freeworld-freetype fonts as follows:
# yum install freetype-freeworld <enter>
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