Leyart's page

Well and so I must confess there's a big issue within the book.
A lot of things are put in the book without even explaining them or explaining them later.
How can a novice understand what a Supernatural or Extraordinary ability is by reading the book as it is given?
It seems that the book has been wrote with advanced player in mind, not players that face the rules for the first time.
I can also feel a complete lack on how a Master should behave and manage not a campaign but even the simplest of the quest.

Thanks to you both, the table on the glossary was EXTREMELY handy, a pity I wasn't able to find it in the book or maybe I was just negligent...
Now it's clear, thank you so much!

Hello, mine is a silly stupid question of clarification, I have just started reading the Pathfinder manual and there's this point I can't get.
What's the REAL difference between a Supernatural & Extraordinary ability?
Everything I was able to find was this:

Supernatural Abilities (Su): Using a supernatural
ability is usually a standard action (unless defined
otherwise by the ability’s description). Its use cannot be
disrupted, does not require concentration, and does not
provoke attacks of opportunity.
Extraordinary Abilities (Ex): Using an extraordinary
ability is usually not an action because most extraordinary
abilities automatically happen in a reactive fashion.
Those extraordinary abilities that are actions are
usually standard actions that cannot be disrupted, do
not require concentration, and do not provoke attacks of
opportunity.

which is fine for me. But then confusion arises,for example here:

Paladin Aura of Courage (Su)
vs
Fighter Bravery (Ex)

what's the difference in terms of use?
Can someone be so gentle to explain me the differences during combat/gameplay?
Thanks in advance and sorry for my bad English, I am Italian...