Control points are the anchors of a vector curve. Their position and their handles decide how the line runs between them.
After digitizing, every contour can be adjusted through its control points without the curve turning angular. Fewer, well placed points give a smoother line than many crowded ones.

Digitize sewing patterns without tracing.
Test PatternScan Pro free for 14 days with the full feature set. You need your smartphone, a printer and one pattern you always wanted digital.