This is how a piece of printed material is held together. Types of binding include <a href="http://www.supercooldesign.co.uk/index.php/default/glossary/saddle_stitching/" title="saddle stitching">saddle stitching</a> and <a href="http://www.supercooldesign.co.uk/index.php/default/glossary/perfect_binding/" title="perfect binding">perfect binding</a>.
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