Slot Knowledge

How Do Slots Work?

Original Liberty Bell Slot Machine

Modern Mechanical Slot Machine

Slot machines were first invented by Charles Fey in San Francisco, California, USA. Slot machines were mechanical devices that would spin and have an outcome. Since the slot machines were fully mechanical, they had to be precisely machined to only have a certain amount of winners. Mechanical slot machines are still found in land-based casinos today, often referred to as ‘One-Armed Bandits’ due the handle on the side. Today these mechanical slot machines use computer chips to determine the outcome but their appearance is different that of a video slot machine due to the mechanical nature.

Video Slot Machine

Whether you play a mechanical slot or a video slot, they operate the same way: a Random Number Generator, known as a RNG, calculates the outcome and the reels on the slot machine display a set of symbols based on the RNG outcome.

Mechanical Reel Strips

Both mechanical and video slot machines have reel strips, but mechanical slot games are generally limited by 22 reel stop positions (including blanks if they exist in the particular slot game). Video slot games generally have from 30 up to 300 or more reel stop positions depending on the slot game. Mechanical slots generally have to weight the likelihood or frequency of each position on the reel to create large variations in payout while video slots generally have longer ‘virtual’ reel strips.

Slot Machine Paytable

The outcome of the displayed stops on the slot are then analysed against a paytable (i.e. 3 cherries pay 20 credits). The paytable and the frequency of the symbols determine your overall play experience but there is deviation between the forecasted distribution and the actual outcomes that determine your winning or losing experience. This is what the ‘gambling’ aspect of the slot game is: deviation. This is because although a slot might be programmed to hold 5% of the bets on a long term average, you can expect to experience this deviation as winning or losing on the slot machine over a short period of time.

Slot Game Play

Slot games are designed with many different features to create lots of different experiences for players. Some slot games are designed for smaller frequent wins, while others are focused on bigger wins less frequently. This is often referred to as ‘volatility’, however the player experience can be far different than what the slot is programmed for.

In general there is a basic formula for what the slot game returns to the player: all possible wins – all possible losses / all outcomes = the ‘hold percentage’ of the game. 100% – hold percentage = the player return percentage.

Slot companies utilize a lot of different play mechanics to vary the experience to players. Generally there is a base slot game + the slot’s bonus features to determine the return to the player.

Our focus will be to inform the player of different slot player bonusing methods to help identify games that will appeal most to you.