Why do pitches "curve" How to reed spin

Why do pitches curve and how do you reed spin

a ball curves because of sidespin on it. so generally, if you see the seams spinning like a top its a curveball.

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A curveball will produce red lines (the seams) that appear to move toward the batter (from top to bottom).

NY Times article
http://www.nytimes.com/imagepages/2008/03/03/sports/20080303_SANTANA_GRAPHIC.html

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A curveball will produce red lines (the seams) that appear to move toward the batter (from top to bottom).

NY Times article
http://www.nytimes.com/imagepages/2008/03/03/sports/20080303_SANTANA_GRAPHIC.html
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very seldomly in youth baseball do you see an actual 12-6 curveball, most of them are slow slider-type pitches. im just giving him the info he needs at his age. as you get into varsity level you may have to pick up the perfect 12-6 spin.

Many times it will tip by popping up first out of the hand, you won’t see the fingers, fb you see fingers, slider spins to a dot.

or the pitcher will drop or raise his arm angle and if he drops he will over suppinate and you should be able to pick that up.

You will generally see a red circle, a wider one is a big looping curve but a tighter one like the dot mentioned above creates a sharper later movement.