Below is a series of terms commonly described or discussed when it comes to online slots.
Bonus slots - Slot machines which offer bonus games when certain combinations hit to provide a bonus game with an additional payout.
Hit - A win on a slot machine is often called a hit.
Hold percentages - The opposite of the payback percentage. The hold percentage on a slot machine with a 96% payback percentage has a hold percentage of 4%, holding $4 of every $100 played over time for the casino. Like the payback percentage, this is calculated over thousands of spins.
Loose slots - Slots that return a high percentage of the money played to the players. Also called generous slots, or hot slots. As opposed to "tight slots".
Payback percentages - The amount of money, in percentage form, that a slot machine pays back to the players over time. For example, a slot with a 96% payback percentage will return $96 of every $100 wagered on it over time. This is a long term number, calculated over thousands of spins.
Payline - The line, or lines, across the screen on a slot machine that show where the symbols have to land in order to win. Most slot machine games are defined by the number of reels and the number of paylines.
Payout - The amount of money won on a given winning spin. The amount of money that is paid out.
Pay table - The line, or lines, across the screen on a slot machine that show where the symbols have to land in order to win. Most slot machine games are defined by the number of reels and the number of paylines.
Progressive ticker - This is the place that shows you how much the progressive jackpot is worth on the slot machine. Not all slot machine games offer a progressive jackpot, and those that don't won't have a ticker.
Random number generators - A computer that constantly generates new numbers that are assigned to each stop on a reel in the slot machine. When you pull the handle or push the spin button, the random number generator tells the reels where to stop. These are completely random. A random number generator is also often abbreviated to "RNG".
Reels - The reels are the mechanical wheels inside of a slot machine that spin and show the results of a spin, win or lose. On newer video slot machines, these reels are simulated; they're just videos of spinning reels.
Slant top - A slot machine that is wider and shorter than normal slot machines. Slant tops are becoming more popular in casinos and are replacing a percentage of traditionally sized slot machines.
Slot machine - Any gambling machine found in a land based or online casino that has spinning reels. Some of these have real reels, while others just have pictures of reels that spin, like a video game. Video blackjack, video keno, and video poker have similarities to slot machines, but they're not really considered slot machines since they don't have spinning reels of any kind.
Static jackpot - A fixed payout for a jackpot that never changes. As opposed to a progressive jackpot, which is constantly increasing.
Stop - Anywhere a reel can stop is referred to as a stop. This includes stops on the symbols and usually stops between the symbols, which are often called blanks.
Symbol - The pictures on the reels. Slot machine symbols can be pictures of fruit, animals, pyramids or any other thing based on the theme of the slot machine.
Tight slots - Slot machines that pay back a low percentage of the amount played to the player. As opposed to "loose slots".
Video slots - A slot machine with a video screen that generates a picture of spinning reels, as opposed to a slot machine with actual physical reels. All online slots games are video slots by their very nature.