Online slots vary in layout, but they all share a basic structure: the grid. This grid consists of reels (the vertical columns) and rows (the horizontal lines). How the game decides you have won depends on the specific mechanic being used.
Paylines and Ways-to-Win
Traditional slots use paylines, which are fixed patterns (straight, zig-zag, or V-shaped) that the game checks for matching symbols. If the required symbols land exactly on that line, you win. Modern slots often use ways-to-win, where symbols only need to appear on adjacent reels from left to right, regardless of their vertical position. Additionally, cluster or grid games ignore lines entirely, awarding wins when groups of matching symbols touch each other horizontally or vertically.
Special Symbols
Most games include Wild symbols, which act as jokers and substitute for other symbols to help complete a winning pattern. Scatter symbols are even more powerful; they usually do not need to be on a payline to trigger a win and are the primary way to unlock bonus features.
You can always find the exact winning patterns, symbol values, and required combinations inside the game's internal paytable.