There are two types of booklets/catalogs: saddle-stitched and perfect-stitched.

A saddle-stitched booklet
is a booklet in which multiple pages of text are folded in half and bound together with wire. It is mainly used for booklets, pamphlets, floor guides, etc.

A perfectly bound booklet
is a booklet in which all the pages of the text are superimposed and fixed by applying glue to the spine and pasted on the cover.
It is mainly used for paperback books and magazines/product catalogs with many pages.