The first thing you need to understand about casino 'odds' or 'house edge' is that they are essentially the same thing. Every gambling game there has casino odds or a house edge, some of which are better than others. And by 'better' we mean that while they still favor the casino, they favor it less so which means that you - the player - have a greater chance of winning or beating the casino. Odds are usually displayed as a ratio (2:1) while house edge is displayed as a percentage.
For instance, the odds or house edge of a lottery/bingo style of gambling game like keno are said to be about 20 percent. What this means is that in the long run for every $1 you wager on keno, the casino will keep 20c while you win 80c. In the gambling world these odds are considered to be very poor which is why casinos love these games and hope you do to. The key to successful gambling is to find games that offer the best odds (of winning), i.e. games with the lowest house edge.
The good news is that two gambling games that fulfill this requirement also happen to be two of the most popular in both land and online casinos around the world. One is blackjack and the other is craps. If you play blackjack following 'basic blackjack strategy', you should reduce the house edge to almost less than 1 percent which means that in the long term you should come out ahead. Similarly, by sticking to certain bets while playing craps, you should increase your odds of winning.
For instance, if you've ever wondered why 7 is such a key number in craps here's why. There are always 36 possible outcomes from two rolled dice. However, the one number that can be made from the most number of outcomes is 7 (1+6, 6+1, 2+5, 5+2, 3+4 and 4+3). This means you have a 1 in 6 shot (36/6) of throwing a 7 as opposed to a 1 in 18 shot of throwing a 3. Hence a craps 'pass line bet' has the highest odds of paying out which is why it is the most popular bet.