Q. What is the bonus pool and how are bonus points acquired? A. The
Bonus Pool is an
accumulation of points that every
player receives whether they're online
and playing or not. They're
essentially used as a means to help
give a player a catch-up boost if they
haven't played in a while. The pool
does have a cap but it increases
slowly until the end of a season.
Q. How is the bonus pool used in competitive play? A. When you
achieve victory against another
player, you are awarded a certain
number of points. The Bonus Pool
points will match the number of points
you received for winning.
For example: If you were to have a
Bonus Pool of 30 and you win a match
that would normally give you 10
points, points will then be pulled
from your Bonus Pool to match those 10
points and you'll be awarded 20 points
for winning that game. Your bonus pool
will then sit at 20.
Best Answer
The number next to that shield is your "achievement points". You earn them based on the point values of various achievements you have completed. These achievements include the ones from single player as well as multiplayer. Go to the achievements tab of your profile for more information on the achievements you have and how to earns the ones you don't.
If you meant the number next to your username (which is not where the arrow appears to be pointing), that is your player identifier. It is used by battle.net to distinguish between players with the same player names.