Modifying Existing Direction Lines
Anchor points are composed of two elementsthe anchor point and direction lines. The anchor point is the fence post that connects segments together. The direction lines influence the amount of curve applied to the segment. The further away a direction point lays from the anchor, the more aggressive the curve. Conversely, the closer the direction lines lay to the anchor point, the less the curve. If an anchor point does not have any direction lines, it is said to be a straight anchor point.

Modify Existing Direction Lines
Open a document that contains a path, or create a new path.
Select the Paths palette, and then select the path you want to modify.
Select the Direct Selection tool on the toolbox.There are no additional options for the Direct Selection tool.
Click the very end of the direction line, and then drag to change the curve of the segment.
Hold down the Alt (Win) or Option (Mac) key, and then click at the very end of the direction line to break the line at the anchor point.This lets you independently control each end of the direction line, as it extends out from the anchor point.
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