Prepress is a term used in the printing industry to describe the process a document must go through before it can be printed. Although it's usually used in connection with making the plates used in a printing press, prepress can also refer to the process of making a document ready for print in any environment, such as through a laser or other digital printing format.

The steps that are considered part of the prepress process vary from company to company, but generally the steps of proofreading, editing, layout, scanning, and color separation are major prepress steps. Some companies may consider the layout and other graphical tasks as part of a graphic design department. Other steps in prepress include converting any digital files into a format that is usable by the printing company, for example, distilling a document into Adobe® PDF (portable document format).

The usual path that a document takes, from creation to prepress to printing, generally follows three steps. First, the document is created by an author, graphic designer, or other creative professional. Then, the document is sent to prepress. While being examined by a prepress professional, the document goes through many stages, including:

• proofreading for spelling and typing errors,
• making sure all pictures and other graphics are in a suitable format,
• separating the colors for printing on a color press that's two to four colors,
• checking that all fonts are coming through correctly, and
• checking general layout guidelines, such as margins and paper size.

Finally, the document is edited and ready to be printed on a printing press. A printing plate is created and a proof, one copy used as an example, is made. The proof will usually be checked by the prepress staff, and if it is satisfactory, the document may be printed.

Prepress has become easier since the advent of desktop publishing, and often the work of several prepress staffers can now be done by only one person. Sometimes, the prepress work is done by the graphic design department along with the composition of the documents.