Recommended reading...

Spydermonke

http://wiki.worldoftanks.com/Battle_Mechanics

There.

I'm surprised there aren't a billion threads just like this.  It probably helps to understand the game mechanics if you are frustrated with some of the features of the game.  That way you can get them to work FOR you as intended.  

Vitalis55

Excellent site for WoT info. I knew of the site but had not yet visited it. Thanks for posting the link here.

 

I would especially like to point out one bit of advice from the site regarding what you won't get xp for.

1. 
   The special bonus for "killing all enemy tanks" does not exist! It will be more rewarding FOR YOU if you help your team to capture the base rather than wasting time hunting one lone enemy.

New players should really take this to heart.  Kills make for a pretty stat but being of best use to your team is the primary objective.  The most kills in a match I have is 10 on a AT-1 tank destroyer but it doesn't mean much.  Many of the kills don't come without a team effort.  You might finsih off a tank with already low hp or kill a full hp tank that a team mate has occupied it's attention while you kill it.  It's all about the team.

 

Just wanted to throw that in there.  Thanks again for the link.