Photoshop provides multiple Pen tools. The standard Pen tool draws with the greatest precision; the Freeform Pen tool draws paths as if you were drawing with pencil on paper, and the magnetic pen option lets you draw a path that snaps to the edges of defined areas in your image. You can use the pen tools in conjunction with the shape tools to create complex shapes. When you use the standard Pen tool, the following options are available in the options bar:
Auto Add/Delete, which lets you add an anchor point when you click a line segment or delete an anchor point when you click it.
Rubber Band, which lets you preview path segments as you move the pointer between clicks. (To access this option, click the pop-up menu to the right of the Custom Shape icon.)