Using the blend modes in Photoshop

Knowing how to use the Blend mode in Photoshop is a powerful tool.  Know what those modes do and how they work is even more important.  The link below talks about these modes and how they work.
http://livedocs.adobe.com/en_US/Photoshop/10.0/help.html?content=WSfd1234e1c4b69f30ea53e41001031ab64-77e9.html.weeblylink_new_window