Create a Corner Point in Adobe CS5 Illustrator
To alter a curve into a corner in Adobe Creative Suite 5 (Adobe CS5) Illustrator you have to change the direction of a path from being a curve to a corner. A corner point has no direction lines and allows for a sharp directional change in a path.
You can switch from the Pen tool to the Convert Anchor Point tool to change a smooth anchor point into a corner point, but that process is time-consuming. An easier way is to press the Alt (Windows) or Option (Mac) key — the Pen tool temporarily changes into the Convert Anchor Point tool — while clicking the anchor point.
To change a smooth anchor point into a corner point by using the shortcut method, follow these steps:
Create an upward arch.
Hold down the Alt (Windows) or Option (Mac) key and position the cursor over the last anchor point (the last point that you created with the Pen tool).
When the cursor changes to a caret (that’s the Convert Anchor Point tool), click and drag until the direction line is up to the grid line above.
Release the Alt (Windows) or Option (Mac) key and the mouse button, move the cursor to the grid line to the right, and click and drag down.