KBBonjourSweetheart is a great font style that allows you to quickly give an artistic, decorative, playful, handwritten look to any text string.
The KBBonjourSweetheart font will integrate quickly into your system via its built mechanism. Mac OS X comes with pre installed font styles and KBBonjourSweetheart will simply be added to your pre existent library.
To learn more about dealing with fonts on Mac OS X you can easily access the Apple support page HERE.
NOTE: The KBBonjourSweetheart font is free for personal use only.