see Headband

a decorative strip of coloured material glued to the bottom of the spine of the book block of a hardback. Always used in conjunction with a headband.

A true headband consists of coloured threads entwined tightly round a core of vellum backed with leather, and is sewn through the sections, filling the gap at the spine between the bottom of the section and the edges of the boards. It thus helps to prevent the sections collapsing through the effect of gravity, and also serves to lessen the damage done when the book is pulled off the shelf by its headcap. Imitation headbands, which are purely decorative, are merely stuck to the back folds of the sections. The band at the tail of the book is sometimes called the tailband, and both head and tailbands are collectively referred to as endbands.