There are four different types of binding. The most commonly used is called saddle-stitch/wire staple binding.  Most catalogs and booklets are Saddle Stitched. Some magazines or catalogs are Perfect Bound (glued), giving them a spine that normally has some vertical printing on it. Another binding is Plastic or Wire-O Binding. For any project that has perfect binding or coil binding, make sure you give yourself a little extra margin in the spine area. There is another binding called G.B.C which is usually used for sales presentation type materials.