Guild Wars 2

As the title suggests, this is a basic question.
I have played the game since launch and have never had a n interest is craft, just like other games. Probably because I don’t fully understand the need or pros of actually taking time to do them.

With the announcement of the ascended weapons/armor and the want to get a legendary, I am seeking information on the aspects of crafting.
My questions (but not limited to) are;

1) What is the importance of crafting?
2) What are the basic? Like what do I need to know, explain discovery/refine etc.
3) How do I know what tier a material is in my bank.
4) Is crafting actually useful?

Sorry for the basic question but I really haven’t understood the comcept.

Hopefuly fellow player can shed some light on the matter ;-)

1)Gives you Xp + allows you to craft ascended weapons
2)Check out the wiki or there are videos on youtube. http://wiki.guildwars2.com/wiki/Crafting
3)If you go into your bank or to a crafting station it’ll be under the collections tab
4)Yes. You can save/make money with it once you max it if you are smart about it. http://www.gw2spidy.com/ can help you decide what to make for profit.

If you’re leveling a craft I would use this website to help. http://gw2crafts.net/ It has step by step instructions that will tell you how to max it for the least amount of gold (what to buy/craft). It updates based on the trading post every 1 hour… so be careful about refreshing.