Three reasons why we crease.

 

1. To fold card stock easily and cleanly.

2. To eliminate cracking on digital and litho printed work - Digitally printed material is fused to the top of the sheet of paper and as such cracking is much more prominent. That said litho printed matrial, which uses ink may still need to be creased based. Paper grain, weight and type also play a role in if it will crack on the fold without a crease.

3. To create a hinge on perfect boung books, this hinge coupled with side glue will protect the integrity of the book block by moving the week point of the cover up the side of the sheet to the crease.

 

Creasing is commonly called die scoring or platen creasing as well. Scoring is a different process, see our article on the difference between creasing and scoring.