A company—also known sometimes as a prepress house—that provides imagesetter output of digital files. Service bureaus typically form a link between desktop publishers—who compose a document or publication using page makeup software such as QuarkXPress or PageMaker—and printers, who require madeup pages on film for platemaking. Service bureaus typically take the digital files (so long as they're PostScript-compatible) and output them to film. Service bureaus may also handle high-end scanning and digital color separation. In contrast, trade shops commonly use a combination of manual page makeup processes and electronic prepress equipment to assemble film for printing.