The number of reels
Reels or Drums are “patterned” ribbons that rotate vertically in the slot machines to match the inside symbols inside them. In the beginning, they were metal bands that rotated inside the machine, but they evolved to animations that serve to give that extra feel of realism to the game. The number of drums has evolved from the classical 3 drums scheme to more sophisticated designs including 5, 6 and even 7 drums at the same time. The most popular are the 3 and 5 drums slot machines:
3 Reel slot machines
These were the first and most classic slot machines and to appear in bars a long time ago. Players can’t even count how many times they tried to ban them, but that never changed the players’ fondness for those slot machines that turned everyone in the game upside down. Since then, classic slots have been moved to land-based casinos and later to online casinos, but generally, they still have the same shape as they did in the 20th century.
Since classic slots have only 3 Reels, it is impossible for all the fascinating features to fit into them. Most of the free 3 Reel slot games only have the basic symbols, such as wild and scatter, which keeps the game exciting. Some of the modern online 3 Reel games may have bonus rounds and advanced features, but that’s more of an exception to the rule. This type of game is often called “fruit slots” because the first 3 Reel slot machines used to have fruit symbols (and many of them still do). While companies continue to produce new slots on such themes as Egypt and horror, many people prefer to play fruit slots.
5 Reel slot machines
5 Reel slot machines are the most popular slot machines among players. This appeared to replace 3 Reel slot machines and make the game industry more fun and entertaining. While the classic slot games were very straightforward with a limited number of gambling features, all 5 Reel video slots have bonus rounds, special effects, and advanced features. Now the player can find wild and scatter symbols, but stacked wild, symbol cascades, wheel of fortune, expanding wild, and so on; many of the developers have their unique features that make their slot machines stand out.
This category obeys the most technical characteristics of the machine, and allows to distinguish several subtypes of slots:
The absolute majority of slot machines that you can find in online casinos belong to the group of video slots. These games are digital slot machine games that are mostly equipped with five virtual reels and a multitude of paylines and bonus symbols. Most slots also offer you the opportunity to win free spins or bonus rounds or have profit multipliers that you can get through certain symbol combinations.
Fruit Games / Fruit Machines
The most popular slot machines are fruit machines or fruit games. These are often rather simple and have a manageable number of symbols or other extravagant features. The name of this sub-genre of slots is derived from the symbols used, which are mostly fruits and which are supplemented by casino-typical symbols such as stars or 8-balls.
Relatively new to the market are slot machines that tell you a story as you play. Like classic computer games, adventure slots have a narrative that brings you closer to the story and which is told after certain missions have been completed using combinations of reels. Often these slots also have a level system with which you can achieve bigger wins or better bonuses at higher levels.
Slots that use progressive jackpots are also popular. These jackpots are made up of the total deposits made by an online casino and its partners or the operator network and can thus offer winnings in the millions. The disadvantage here is that these slots often offer the lowest payout percentages as the jackpot has to be fed.