Normally, when scrolling using the mouse wheel, the number of lines scrolled per notch or ‘tick’ of the wheel is constant. With accelerated scrolling, the faster you turn the wheel, the more lines you will scroll per tick. Therefore, if you turn the wheel slowly over 5 ticks, you may scroll 30 lines (default 6 lines per tick on Windows), but flicking the wheel very fast over the same five ticks may scroll 50 or 100 lines, depending on your speed.
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