Hi Rahul!

The seam of a closed curve or polyline is the place where the start- and end-point overlap. A closed curve/polyline is nothing more than a curve with the same start- and end-point. The Seam Component allows you to move the seam (or start/end point) of the closed curve to another location.

I believe Rodrigo used the seam component to align both seams to the bottom of the circles. When using the Evaluate Curve component afterwards those points are nicely symmetrical on both circles.

Best,

Arie