Slot machine showing three stars on a small laptop screen.
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While the global iGaming market features a number of fun and immersive verticals, there’s no doubt that slots continue to dominate. This vertical certainly dominates the market’s gross gaming yield (GGY), while contributing the vast majority of games and titles.

However, the slot niche is considerably more diverse than it’s initially given credit for. At, which reviews the best casinos to play online slots in the USA, you can find a brief breakdown of the different types of online slots, which may make it easier for you to select games and enjoy the best possible experience online.

I’ll explain these slot types in a little more detail below while asking what distinguishes them from one another in this highly lucrative marketplace!

#1. Video Slots

We’ll start with video slots, which follow the basic mechanics of traditional fruit machines and effectively replicate this technology online.

Unsurprisingly, video slots are the most common type of all free slots and online casino games, often accounting for as much as 75% of an operator’s published games’ library. There is a good portion of video slots that were inspired by popular video games such as Street Fighter and Conan.

Video slots will feature a certain number of reels (usually between three and five) within a framed grid. The most common layout is a 5x3 reel grid, which will feature a diversity of symbols that can form a predetermined number of winning combinations (or paylines) and variable payouts.

You can decide how many paylines you want to activate during gameplay, before setting your stake amount within a specified range. You can then set the reels in motion, with all results determined by chance and using advanced random number generator (RNG) software.

Video titles are usually the best online casino slots to play for real money, although payouts can vary wildly from one game to another depending on the available betting range and in-play variance.

#2. Megaway Slots

The top casinos with the best online slots tend to feature a broad diversity of games, including so-called “Megaways slots”.

This vertical subset utilizes a unique ‘Megaways’ random reel modifier mechanic, which was previously developed by the Australian developer Big Time Gaming and has since been licensed to a number of operators and software houses.

But how does the Megaways random reel modifier mechanic impact slot titles and change the fundamental nature of the game? Well, it can change and increase the number of reels and symbols that appear on the screen when triggered, usually at random and following a standard spin.

Due to the addition of reels and new symbols (which may appear stacked on specific reels), the Megaways mechanic dramatically increases the number of potential paylines and winning combinations. For example, some slots in Big Time Gaming’s library offer a staggering 117,649 ways to win, while others developed outside of the brand under licensing have exceeded this number.

At the higher end of the scale, some Megaways titles feature a mind-boggling 248,832 ways to win, while experimenting with such titles is key when learning how to play online slots for real money.

#3. Classic Bar Slots

Bar slots definitely have a nostalgic and retro vibe, as they typically feature three reels that are displayed in a simple, 3x1 reel grid. At the same time, they tend to feature classic and well-known symbols, such as melons, oranges, cherries, and lucky sevens.

Then there’s the iconic ‘Bar’ symbol, which often triggers significant payouts and highly rewarding payouts both on and offline.

Bar slots typically boast a high return to player (RTP) rate of 96% or above, which means that you can recoup $96 for every $100 on average through such games. At the same time, this type of low-variance slot may also be featured as part of the best online slot bonuses, specifically those that offer a predetermined number of free spins.

Preferred by casual and older players online, bar slots often deliver frequent, albeit relatively modest, payouts, while they’re also highly accessible and easy to play!

#4. Jackpot Slots

We’ll close with jackpot slots, which are also synonymous with so-called “progressive” slot games. The latter form part of a network of slots that combine to provide limitless jackpots that are won sparingly, but remain capable of triggering seven or even eight-figure payouts,

As for standard jackpot slots, these titles combine increased risk and higher stakes with the promise of bigger rewards, with higher variance gameplay compensated for by larger-than-average payouts.

In terms of base gameplay, jackpot slots look and play much the same as standard video titles, although their RTP rate range can often vary between 89% and 95%.

This definitely translates into fewer base game wins, but you can more than makeup for this in instances where you’re consistently able to wager at a higher amount (which is often a prerequisite if you’re to win the biggest prizes) and make hay during bonus rounds!​