Technical Definition-A single image on a screen and the unit of time used in fighting games. Fighting games run at a fixed 60 frames per second to simulate motion. So 1 frame = 1/60th of a second or 0.0167 seconds. The average human reaction time is around 280 milliseconds and the median reaction time is around 270 milliseconds. This converts to 16-17 frames, meaning people can physically react to 16 or 17 frame moves (in a vacuum). Realistically, players will not react to sub 20 frame moves every time during a real match.
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