Since slots were popularized on casino floors more than 50 years ago, they have gone through many changes that made them more entertaining and profitable for players. From mechanical 3-reel machines to 5 and 6-reel video and 3D slots, the variety of slot games in land-based and online casinos will satisfy every fan of this exciting game of chance.
The range of themes, styles, and genres is overwhelming with dozens of new titles being released every single day. To help players choose the best game for themselves, however, we can divide slots into several major types, namely classic slots, video slots, and slots with progressive jackpots.
Classic 3-Reel Slots
The first slot machines had only 3 moving reels with several types of symbols that could form a winning combination. Usually known as classic slots, there are now many virtual games with similar vintage design and look. They rarely offer any bonus features or symbols with special functions such as wilds or scatters. What many of them have in common is the classic theme, the simpler interface, and the traditional symbols such as fruits, Bars, and lucky 7s that land on the reels.
This is a very common style of machine and it allows you to play from 1 to 3 coins per spin, although some variations allow up to nine coins per spin. The more coins you insert, the bigger your prize will be (proportionately). This does not always apply to the jackpot, however.
Classic Slots with a Single Payline
These slots are usually what most people picture in their minds when thinking of retro slot machines. They have a single payline that runs across the middle position of the three reels. This horizontal line is players’ only opportunity to win – they need to get 3 symbols of the same kind on this line to receive a payout. Typically, players can bet 1, 2 or 3 coins per spin and the maximum number of coins unlocks the highest payout in the game, i.e. the jackpot.
Note that the jackpot is often disproportionally higher than if we bet 1 or 2 coins, so playing with max bets is certainly worth it. To adjust their stakes to their bankroll, however, and avoid overspending players can simply reduce the coin denomination – from $1 coins, they can bet $0.25 or even less, depending on the particular game. Another aspect of these games is that they rarely have any special symbols. The only exception is the addition of a wild in certain slots. It spices up things and increases the winning potential of the game.
Multi-Line Classic Slots
As their name suggests, these slots offer more than one way to get a winning combination. Although they have only 3 reels, they may have 3, 5 or even 9 paylines crossing them – three horizontals, two diagonals, and more interesting patterns. The purpose of the additional paylines is to give players more chances to score winning combos. These paylines may be fixed or activated by the player – note that for each additional line, you will need to bet a coin.
Once again, most games of this type allow up to 3 coins to be wagered on a line and the different coin sizes give more flexibility when adjusting the stakes. It is crucial to choose a machine with a wide range of coin denominations – otherwise, you can quickly run out of money. For instance, we play a classic, 5-payline slot with 3 coins and denominations from $0.10 to $5.00. If we want to make the most of the game and qualify for the biggest payouts, we should activate all 5 lines and bet the maximum number of coins – therefore, we will wager 15 coins per spin.
If we stick to the minimum coin size, each bet would cost us $1.50 but if we decide to increase the stakes and choose the max coin size, we will end up betting $75 on each spin. As you can see, adjusting the bets is crucial even when we play retro slots.
While some casino players find classic, 3-reel slots entertaining enough, most fans of the game prefer the more modern alternatives that started appearing several decades ago. They feature more reels, more paylines, and more interesting symbols and bonus rounds that take the gaming experience to a whole new level. Video slots feature much better graphics, enhanced audio and visual effects, and sometimes, even 3D animations.
This allows for the development of more complex storylines, the addition of various characters, and the creation of innovative bonus features and games. Along with the free spins rounds that are commonly found in most video slots, there is also a wide range of special features and mini games that trigger randomly or upon a specific achievement during the base game. This could be a matching symbols game, a wheel of fortune with different prizes on it, a game where players pick 3, 5 or more items to receive a corresponding reward, etc.
Traditional Reel Structure
The most common reel structure in video slots includes 5 reels and 3 rows of symbols on them. Many game developers have also introduced 5×4 slots where there are 4 positions on each reel so, in total, there are 20 symbols that land on the screen with each spin. The addition of rows effectively allows for more paylines to be included in the game, hence more opportunities to form winning combinations.
Slots with 5 reels typically have 9, 10, 15, or more paylines that cross the reel grid in different patterns – there may be straight lines, diagonals, V or W shapes, and many more. There are even games with 50 and 100 paylines, which are not fixed and players can activate as many lines as they wish and can afford. As we have said above, the more paylines, the more opportunities to score a win. However, players are always advised to carefully adjust their bets unless they wish to wager their entire bankroll within 15 minutes.
Don’t think that all video slots have 5 reels, though. Some of them come with a more innovative structure such as 6 reels and 4 rows. The number of available paylines would vary across different games, of course, but we can expect to play with at least 20 lines on top of plenty of special symbols, bonus features, free spins, and more exciting things.
Unconventional Reels and Payout Systems
The variety of video slots in land-based and online casinos is, indeed, overwhelming and we can find all kinds of interesting games with 5, 6 or even more reels, multiple paylines, and symbols with different functions. But there are some quite unique slots that completely eliminate the traditional notions of reels or paylines and introduce brand new ways to play and form winning combinations.
Let’s start with the video slots that have a non-standard reel structure – rather than the traditional square shape, the reel grid may resemble a diamond or a kite. In this case, each reel would have a different number of positions on it. For instance, we may have a game with 5 reels and while the first and fifth reels have 3 symbols, the second and the fourth contain 4 symbols. The middle reel would then have 5 symbols. There are also video slots with pyramid shapes, where the gameplay is even more unconventional.
In addition to these types of games, there are also a great number of video slots with non-traditional paylines. They may pay for combinations in both directions (known as all ways or both ways win slots) in contrast to the regular paylines where symbols need to appear from the left to the right. An even more interesting concept is the so-called way wins – there are no fixed paylines here. Instead, combinations are formed by identical symbols falling on any position of adjacent reels. Once again, the combinations need to start from the leftmost reel.
In this type of video slots, the number of possible ways to win is much higher than in regular slots. For instance, we have a 3 reel slot – the possible ways to win can be calculated very easily. They are exactly 27 (3x3x3) because there are 3 reels with 3 rows of symbols. If we have a regular 5-reel, 3-row video slot, then we have 243 ways to win (3x3x3x3x3). Following the same logic, 5×4 slots have 1,024 ways to win, while 6×4 slots have 4,096 ways to win.
Slots with Progressive Jackpots
The vast majority of classic and video slots have fixed payouts, which are multiples of the coin bet and can be seen in the paytable of each game. For instance, if a 3-symbol combination pays 10 coins (10x), 4 symbols would pay 15 coins (15x), and for a 5-symbol combo, we would get 25 coins (25x). The top payout in each game is known as the jackpot payout and it works in the same manner, although the amount of the prize is usually much higher – 600x, 1,500x, 10,000x, etc. Its amount, even though it depends on the size of our bet, is fixed.
Things are much different when it comes to progressive slots, however. These are slots where the jackpot constantly increases and may reach 6 and 7 figures, depending on the particular game. In fact, the jackpot rises until it is hit by some really lucky players, which, as you can imagine, adds a whole new appeal to these games.
How Progressive Jackpots Work
For those who are not familiar with the term, progressive jackpots in slot games resemble the jackpots in lotteries. They are offered in games that are linked in a network and a small portion of each bet placed on these games goes to “feed” the jackpot. The exact amount the jackpot rises with is determined by the house (the casino or the game developer) and is usually up to 10% of each individual bet placed in the game.
Over time, the jackpot progresses until it is won by a player – then it resets to its initial amount, known as the seed value. This seed amount is typically also collected by a small percentage of each bet. In most cases, the large part of the contribution goes to the progressive part of the jackpot while only a small portion is used to build the seed value. For instance, we play a progressive slot and bet $1 on each spin – 10% or $0.10 of this amount would be taken for the jackpot. Of this, $0.01 would go to the seed, while the other $0.09 would contribute to the jackpot pool.
Of course, the initial amount is usually secured by the casino or the game developer, while the rest of the jackpot amount should be always readily available. This is why many casino software providers manage to pay out even the largest jackpots in full. It is also important to understand that due to the nature of these jackpots, their size correlates to their popularity – the more people play a certain progressive slot, the larger the jackpot will be and the faster it will build over time.
Qualifying for the Progressive Jackpot
The next important thing to mention about progressive jackpot slots is that there are usually certain conditions that must be met in order to qualify for the jackpot. In most games, players can qualify only if they wager the maximum amount of coins. If they play the game with fewer coins, they would only receive the regular payouts for each of the winning combinations. Other slots require players to place a side bet, which unlocks the progressive jackpot. Usually, these side bets are around $0.50 to $2.00, which is acceptable for most players. However, they must be placed on each round so, eventually, they would probably increase the cost of the game by a significant amount.
In most progressive slots, the jackpot is won after hitting the highest-paying combination in the game. This could be 3 cherries in a classic, 3-reel slot or more often, 5 high-value symbols of the same kind in video slots. Players should also be prepared that there are certain slots where the jackpot is received only after triggering a special jackpot game. For instance, players get 3 scatter symbols and they activate the jackpot game, which is a wheel of fortune – on it, there are different cash prizes, multipliers, and the best prize is the progressive jackpot.
As you can see, progressive jackpots are not so easy to hit. If players want to try their luck, however, they need to make sure they can qualify for the jackpot. They should also be willing to pay more for the opportunity to become a millionaire.
Wide Area Network Progressive Slots
When the first progressive jackpots were introduced in the world of slot machines, they were not as exciting as they are today – only the bets on one particular machine contributed to its progressive jackpot. Later, casinos started linking the different machines into a casino-wide network and the jackpots started to rise much faster and to much higher amounts. Nowadays, progressive jackpot networks connect thousands of games and even more, allowing millions of players to contribute to the same jackpot.
This applies to both slot machines in land-based casinos and to online casinos that offer the same software platform and host the same games. The interactive nature of these games means that many people can play for the jackpot at the same time. In fact, it is possible for two players to hit the jackpot simultaneously – of course, what looks simultaneous to us has probably happened within several milliseconds. However, the game software can always determine the actual winner and the exact time of winning the jackpot.