Offering multi-million dollar payouts, the slot machine has become an integral part of the land based and online casino landscape.


There are two competing claims to who brought out the first slot machine. In the 1890's Charles Fey, an inventor from San Francisco developed the Liberty Bell game. This consisted of three spinning reels, each one containing the card symbols diamond, hearts, and spades, plus an image of the cracked liberty bell, which paid out 50 cents when it lined up on the reels. The original machine is still on display at the Liberty Bells grill in Reno, Nevada. The other claim is from Sittman and Pitt of New York, whose machine had poker cards around the reels, with payouts based on the same ranks as poker hands.

Arcade game developer Herbert Mills from Chicago, was certainly the first to add symbols like cherries plums and lemons to the reels around 1907. With these early machines, an assistant had to be on hand to pay out winnings, and in some states, to get around gambling laws, payouts were in the form of beers, cigars or whatever was on sale where the machine was placed.

Slots machines gradually became more sophisticated and in 1963, the Bally company brought out Money Honey, the first electromechanical machine. This featured an automatic payout of coins into a hopper below the machine, removing the need for an attendant, and by the mid-1970's the first video slots were coming out. It was in 1994 that Three Bags Full, the first computerized slot game with a bonus round, was launched and by the end of the 20th century, the new online casinos were offering a range of advanced slots which are now enjoyed by millions of players worldwide each day.

From the 1970's slots were particularly popular in the UK, USA and Australia, while online casinos have made them a huge success in many more countries, and they rank alongside poker, table games and sports betting as the biggest form of online gambling. Now there are slots of all types, from 3D, to movie themed, multiplayer tournaments and a whole myriad of winning combinations. The history of slots continues to be written as more and more games are released almost weekly.


It is advantageous to know some of the basic terminology used with slots machines and the list below can help anyone new to playing these games get started with confidence.

Bet:  The wager placed on the outcome of a game.

Bonus Feature: An extra feature additional to the payouts received by lining up matching symbols. Examples include Wild symbols and free spins rounds.

Free Spins:  A number of spins ranging from 1 to 20 or more, that play out automatically, ideally accumulating wins as they do so.

Gamble Feature:  A bonus game during which players make a simple 50/50 choice, doubling their win if correct and losing it if incorrect. Further guesses can double the win again and again.

Jackpot:  The maximum possible payout on any particular slot machine.

Max Bet:  The maximum number of coins that can be bet on a spin of the reels.

Payline:  To get a winning combination, symbols must fall along a payline which runs from one side of the screen to the other, in different patterns. Some machines have as few as three paylines, others have 100 or more.

Progressive Jackpot:  A jackpot prize that grows each time a player feeds money into the machine and is won by a single player.

Reels:  Several adjacent, vertically spinning barrels, with various symbols upon them. The basic aim of a slots game is to get these reels to come to a stop with symbols lined up in a winning combination.

Scatters:  Special symbols that do not have to be lined up on a payline to create a win, often triggering a bonus round.

Wilds:  A special symbol that replaces other symbols to help create wins.

Winning combinations:  The different arrangements of symbols that will pay out a prize to the player. Online slots can have hundreds or even thousands of these combinations.


Most video slots have at least two rounds, a base game where the reels spin, and one or more bonus rounds. The aim during the base game is to line the symbols along the paylines in winning combinations. The bonus games can take multiple forms and each game features different ones. With wild symbols, scatter symbols and multiplier symbols, there are many ways for them to line up and create a win.

With each game being so different, it is a good idea to learn about each slot before playing it, and here is an introduction to some of the basic types. Most games feature a Paytable that explains how to play and what combinations will win.

3-reel slots: These are the traditional looking games, based on the slots that have been around for many years in bars and land based casinos. They tend to have up to five paylines.

5-reel slots: These are the more advanced video slots games which have bonus rounds, multiple winning combinations and lots of paylines.

Multiline slots:  Slots with more than 25 - 30 paylines, which can cost more to play, but have higher payouts.

Progressive slots:  A game where the maximum payout grows the more people play it. Each time someone pays to play the game, a percentage of the money goes towards the progressive jackpot until it is won by a single player. some games now feature up to four jackpots of different values.


The outcome of a spin on a slots machine is totally random, and unrelated to the outcome of any previous spin. Computer programs ensure that it is not possible to influence any results, so there is no skill that will change where the symbols will land. There are still a number of ways to make playing slots even more fun, and extend your bankroll further and for longer.

Players are spoilt for choice when it comes to the range of slots games available, and each individual should choose ones that suit their own personal preferences and budgets. Always look at the paytable to determine what the minimum and maximum bet sizes are, what prizes can be won, and the chances of hitting the jackpots. Some games payout lots of smaller prizes while others pay just a few, bigger prizes, so it's up to the player to decide which they want to try out. Games are often based around a particular theme, which can include anything from ancient civilizations to outer space, monsters to superheroes, and warfare to enchanted forests.

You should also look at the bigger picture before embarking on a slots-playing career. Which online casinos suit your budget and spending habits? Where can you get the best and most valuable promos to help fund your playing style? You can find all the information you need on all the leading slots-providing online casinos on the OCR site.Choosing an online casino that will provide the best bonuses and promotions to help you play more games is always a good idea, while many will offer customers special bonuses just for playing slots games. Which sites will suit your own style and game preferences? Which offer the best selection of slots that match your tastes? All the information needed to select these casinos can be found here at OCR.


  • Never forget that slots are random. It's a fact worth pointing out again, and although some lucky players have become multi-millionaires in one click, these games don't require any skill to play, and not strategy will change that.
  • To win a progressive jackpot, players need to Bet Max. Imagine the dispair you would feel if the progressive jackpot combination came up, but because you were not betting the maximum number of coins, you couldn't claim it!
  • Keep looking for new slots games. Casinos always want to offer their customers the newest and best games, and hardly a week goes by without at least one new game being released. With slots based on just about every subject imaginable (within reason!), players will invariably find some games they have not tried before.

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