In Part III we learnt about reading time signatures from notation - imho, the most useful thing of notation.
In Part IV we're continuing with time signatures, going into detail on triplets. If you wanna Iron Maiden or Metal in general, a triplet feel (1/8th note) is pretttyyy important. It's that galllop-y feel that metalheadss know and love ?
One thing we haven’t covered in this series of lessons is triplets, or three equally spaced notes per beat. They look like what you see in Ex. 1. You can count them “one triplet, two triplet,” etc., or by saying any three-syllable word, but I like the numbers, because it tells me where I am in the bar.
Check out Part IV on Guitar Player here
Quick aside: It's a LOT easier to grasp when you've got a audio example to listen to...Yeah he's playing piano, but it's as good as I could easily find (for now).