section_path: Contemporary publishing/Manufacturing/Printing
section_name: Printing
paragraph_text: Printing
  
  Some books, particularly those with shorter runs (i.e. with fewer copies) will be printed on sheet-fed offset presses, but most books are now printed on web presses, which are fed by a continuous roll of paper, and can consequently print more copies in a shorter time. As the production line circulates, a complete "book" is collected together in one stack of pages, and another machine carries out the folding, pleating, and stitching of the pages into bundles of signatures (sections of pages) ready to go into the gathering line. The pages of a book are printed two at a time, not as one complete book. Excess numbers are printed to make up for any spoilage due to make-readies or test pages to assure final print quality.
  
  A make-ready is the preparatory work carried out by the pressmen to get the printing press up to the required quality of impression. Included in make-ready is the time taken to mount the plate onto the machine, clean up any mess from the previous job, and get the press up to speed. As soon as the pressman decides that the printing is correct, all the make-ready sheets will be discarded, and the press will start making books. Similar make readies take place in the folding and binding areas, each involving spoilage of paper.
  
  Recent developments in book manufacturing include the development of digital printing. Book pages are printed, in much the same way as an office copier works, using toner rather than ink. Each book is printed in one pass, not as separate signatures. Digital printing has permitted the manufacture of much smaller quantities than offset, in part because of the absence of make readies and of spoilage. Digital printing has opened up the possibility of print-on-demand, where no books are printed until after an order is received from a customer.