Why is it some skateboards are flat and others aren't? and what's best?

I have a C.A.S 30 series skateboard.


specs


deck - 31" x 8" hardwood laminate


truck - 5" indy aluminum


wheel - 52 x 36mm cast polyurethene


bearing - ABEC-5


Graphic silkscreen


what do these all mean??

Why is it some skateboards are flat and others aren't? and what's best?
The reason skateboards are flatter than others is because the concave is different.





The concave is the dip in the board that helps you balance while riding, and help you have more control while doing tricks.











The 31 x 8 means that the board is 31 inches long and 8 inches wide. and ists made of hardwood laminate





The 5" trucks means that the truck is 5 inches wide. and its made of indy aluminum.





The wheels have a radius of 36 mm and 52 mm wide. and are made from polyurethane





ABEC 5 is just the type of bearings





And the graphic was applied to the boaord through silkscreen printing
Reply:you should know you typed it
Reply:"Flat ones" came out in the1980's


"Curved ones" in the late 1990's





Basically the "Curved Ones"

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