Board Thread:Wiki discussion/@comment-4881935-20130327060139/@comment-6301771-20130331005436

Ozuar wrote: Diameter is better for skills with a less defined center (Ex. Brand W), whereas radius is better for skills with a more defined center (Ex. Jarvan W). Further questions? Less defined center? What do you mean less defined center? They're all circles. All circles have a radius. As a game tool, radius tells you the max distance you can place your spell to still hit an opponent. Radius tells you the area of your spell, and therefore how many foes it can hit. Diameter is literally twice Radius. That's all it is.

I don't get how people are trying to debate this. It's mind boggling. Every mathematical formula in the book uses radius. Every single one. Why? Because RADIUS IS MORE USEFUL. The only use for diameter would be to determine whether you could get two enemies within an area (Or blast radius, as it's called) of a spell, and even then, diameter is just twice radius. Double it. Ta dah.