Traits Point
http://wiki.guildwars2.com/wiki/Traits#Trait_tiers
That should answer your questions
http://bad-eu.guildlaunch.com
The Family Deuce. Asuran Adventure Specialists.
You get your first trait point at Level 30, and then an addtional one every few levels until Level 80 where you’ll have a total of 14. Your next point will be awarded at 48.
Each trait line only accepts a maximum of six, each tier accepting two, one for a minor trait and the second for a major trait of your choice from a selection of traits available to that tier. Even then, you have to complete a specific task to unlock each trait, which will be explained by hovering the mouse over the telescope icon next to each trait in the list.
Each tier also unlocks at a specific level. Adept at Level 30, when the system first becomes available to you, Master at 60 and then Grandmaster at 80. Until then, you can’t assign points into those tiers.
Even if you haven’t unlocked any traits, the points are far from useless, as each point in a trait line also boosts a couple of stats depending on the line.
Don’t worry if you assign a point to the wrong trait line. You can also remove that point and assign it elsewhere, or start a clean slate and click “Refund Points”. 
thx a lot guys very useful