"Odds" is the term used to describe the chance or likelihood of something happening or not happening. In terms of gambling, "odds" represent the chance that a person has of placing a winning bet. For casinos, online gambling sites and lotteries, the odds are always in favour of the House, meaning that over time, the House always wins.
The probability of an event is the number of ways the event can occur, divided by the total number of possible outcomes. For example the probability of selecting the Queen of Clubs out of a deck of cards is 1 out of 52, and the probability of selecting any spade card is 1 out of 4 (13 out of 52).Probability allows us to predict how often an event will occur, but does not allow us to predict when exactly the event will occur (randomness).
Randomness in gambling is based on unpredictability and chance. By shuffling a deck of cards or placing a ball on a spinning roulette wheel, casinos are able to create a random (unpredictable) outcome that makes it difficult (if not impossible) for a gambler to accurately predict. Historically, gamblers have formulated strategies and systems to help them predict outcomes of random games. They don't work. Randomness is never influenced by past patterns or events.
Hit frequency is defined as how often a slot machine will have a winning outcome and is usually given a percentage. A hit frequency of 10% means that in the long run, a machine will stop on a winning combination about 10% of the time. Large variations exist between the hit frequencies of slots, ranging between 3% and 40%. Machines with smaller hit frequencies tend to offer larger jackpot opportunities. For machines that offer multiple lines on each spin, the losing combinations will far outnumber the winning ones.
Chance Based vs. Skill Based Games
Gambling is based on the concept of "chance" meaning that the outcome is completely random and that there is little to nothing a player can do to improve their ability to win. In fact, most games and forms of gambling fall under this category.
For example, the game of Roulette is based purely on chance. There is nothing a player can do to become better at winning and there is no way for a player to know where the ball will land. Sometimes you might win, while other times you might lose.
In skill based games like poker, blackjack and sports betting, players have the ability to make decisions that can affect the outcome of the game. For example, knowing player and team stats may put you at an advantage when you make your decision on which team will win or lose. However, the outcome is still random and anything can happen in the game, which keeps a significant level of chance in the game.