The literary equivalent of the fat old guys who sang on the Milli Vanilli
records. In other words, a writer who writes under someone else's name with their consent. The so-called author gets his or her name printed on the cover and receives credit for the writing while the ghostwriter does the actual work.
Celebrity and politician autobiographies are usually ghostwritten, due to the "author" having no writing talent whatsoever. What, you think Jenna Jameson
and Hillary Clinton
actually wrote their books?
Ghostwriters are also disturbingly common in fiction, not that anyone gives a rat's ass that Tom Clancy
doesn't actually write his crappy novels.