Clipping path
From The Glossary of Digital Photography
A line or series of vectors that are drawn around an object in a program such as Photoshop to enable an object to be cut out of the background. A clipping path is similar to a mask. The object and the clipping path can be saved in an EPS file so that the subject can easily be removed from the existing background by a user to be placed on either a white or a new background. In this way, the image can be used with the existing background or a new one. The process is also known as creating a knock-out, since the photographer is generally knocking out the background.
