I am a new adventurer of no basics. Someone can tell me what this xdx+x is? What is a 6d6 damage? Thanks you!

Take a look at the manual.

As far as specifics go, I can't help you as those numbers are based on Dungeons and Dragons (and Advanced D&D) dice, tables and rules and I've never played either (board, paper - whatever).

If you need the info, try posting at the Baldur's Gate II forum. Many experienced, polite and extremely helpful gamers over there.

General rule of thumb: high numbers are good, if you're dishing them out, bad if you're on the receiving end. Also, try to get your character's (both PC & NPC) armor class as low as you possibly can - makes it tougher for enemies to get a good whack in. Good luck!

To cut the long story short, xdy+z means throw x dice, each having numbers from 1 to y, add the total and to that total add z. For example, simple long sword does damage 1d8 - that means throw 1 8-sided die and that is how much damage you deal. (strength and proficiencies will increase this)