I'm having a hard time grasping when I should use this little "function". I'm using Griffith's Intro to Electrodynamics and either he doesn't touch on it enough or I'm missing the point. From what I think I understand I'm to use it when there would be a singularity in a result or calculation(?). Not sure about this. I've been looking around a lot online but can't find anything that explicitly states "You should use this here." Maybe I'll never find it. In any case, does anyone have any pointers?