Video slot games are the most common type of online casino game. They are also the most profitable for casinos. They offer a variety of themes, paylines, bonuses and razzmatazz.

Unlike mechanical slots, which use physical reels, video slots are computerized. They use random number generators to determine the results of each spin.

In the past, players rejected early video slot games because they were bland, lacked animation and bonus events and didn’t seem to have any appeal beyond the mechanical-reel slots that ruled the gambling floor. Those players didn’t trust the computer, and they thought video results could be fixed against them.

The mid-1990s brought a major breakthrough to video slot design. Australian developers devised games that combined five reels with free-spin bonuses and other bonus events. These games had success on the Pacific Rim and prompted U.S. manufacturers to start developing their own video bonusing slots.

A key advance was the creation of virtual reels in a computer chip inside the machine. These virtual reels are similar to the physical reel in shape, but they have a much greater number of positions than a physical one.

This increases the odds of a winning combination because it allows for more symbols to be used in an event. However, it can increase the amount of work a programmer has to do in game math, and it can make a slot more boring for players.

Choosing the right slot depends on many factors, including the game’s theme, bonus events and volatility. Some games have large jackpots, stacked symbols or pick’em bonuses. Others have low hit frequency or use a scatter symbol. It’s best to try them all out before making a final decision.