Reading build guides?

This is a really newbie question, but I just can't figure it out. Why do some skill suggestions in build guides have more than one number (ex: 10 + 1 + 3)? I'm so confused!

In your example (10+1+3):
10 - attribute investment
1 - headgear bonus
3 - superior rune bonus

The +1 is the innate bonus from the helmet (if you look at armor crafters the helmet/headgear already comes with a +1 for a certain attribute). The other +1/+2/+3 is from a rune.