Paths
can have two kinds of anchor points—corner points and smooth points.
At a corner point, a path abruptly changes direction.
At a smooth point, path segments are connected as a
continuous curve. The Convert Direction Point tool . lets
you change an anchor point from a corner point to a smooth point
or visa versa.
To convert a corner point to a smooth point, drag direction lines out of the corner point.
To convert a smooth point to a corner point without using direction lines, click a smooth point.
To convert a corner point without using direction lines to a corner point with independent direction lines, first drag direction lines out of a corner point (making it a smooth point). Release the mouse button, and then drag either direction line.
To convert a smooth point to a corner point with independent direction lines, drag either direction line.