There are many different forms of Bridge:
     Rubber Bridge          Duplicate Pairs
     Chicago                     Team of Four
Though they all have different methods of scoring, the 
basic Trick Score is common to all forms of Bridge. 
A Game is made when the Trick Score is 100 points or more.

TRICK SCORE                         GAME
CLUBS/DIAMONDS 
20 points per trick                   5 Level  5x20 = 100

HEARTS/SPADES 
30 points per trick                   4 Level  4x30 = 120

NO TRUMP 
40 points for first trick then     3 Level  40 + 30 +30 = 100
30 points per trick 

       Pair and Team games are for tournaments while Rubber and Chicago can be played privately at home.  Rubber bridge requires that a team win two games to win the Rubber and get a bonus.
      Once a team wins one game they are on the verge of winning the rubber.  This condition (of having won one game) is called VULNERABILITY.  To be vulnerable means penalties and bonuses are increased.  The use of Vulnerability is in all forms or Bridge scoring.  Below are the bonuses and penalties for NOT VULnerable vs. VULnerable.

BONUSES   NOT VUL                VUL
Part Score             50                     50 

Game                  300                   500 

Small Slam         500                    750 

Grand Slam     1000                  1500

Making a              50                       50 
Doubled Contract 

TOTAL SCORE = TRICK SCORE + OVER TRICKS + BONUSES
When  computing the Total Score add in the appropriate bonuses. 
Example:  3 NT bid and made 5 Vulnerable. 
                                                   Trick Score: = 100
                                            plus Over Tricks:     60
                                           plus Game bonus:  500
                       Total Score:  100 + 60 + 500 = 660
Note: Vulnerable Game bonus is 500 points.

UNDERTRICKS                   POINTS FOR DEFENDERS

NOT		NOT VUL	VUL
DOUBLED		50/Trick	100/Trick

 

DOUBLED	SET	NOT VUL	VUL
	1	100	200
	2	300	500
	3	500	800
	4	800	1100
	5	1100	1400

MAKING DOUBLED CONTRACTS
When a contract is doubled, and made, the 
Trick Score gets doubled. 
2 u doubled and made: 20 x 2 = 40 Trick Score.
40 x 2 = 80 is the Trick Score doubled. 
Add the Part Score bonus: 50 points.
Plus the Making the Contract bonus: 50 points.
Total Score: 80 + 50 + 50 = 180 points. 
It is possible to double a contract into a game. 
2 $ doubled and made:  30 x 2 = 60 Trick Score. 
60 x 2 = 120 is Trick Score doubled which is game.* 
Add the Game bonus: 300 points.
Plus the Making the Contract bonus: 50 points
Total: 120 + 300 + 50 = 470 points.

* Only if the Trick Score doubled = 100 points or
   more is there a  Game bonus.  Over Tricks are
   added after.  ie 2 # doubled making  5 does not
   get a Game bonus. 
   2 # x = 40 x 2 =80 Trick Score doubled
   30 x 2 = 60  Over Tricks
   60 x 2 =120  Over Tricks doubled
   Add the Part Score bonus: 50 points.
   Plus the Making the Contract bonus: 50 points.
   Total Score: 80 + 120 + 50 + 50 = 300 
   You cannot double a person into a slam.  Slams 
   must be bid and made to get the bonus.
   ie 3 u doubled making 3 gets the Game bonus 
   and Making the Contract bonuses only. 
   Total Score: 120 + 300 + 50 = 470